GB2627523A

GB2627523A - Method and apparatus for preparing flakes

Info

Publication number: GB2627523A
Application number: GB2302788.1A
Authority: GB
Inventors: Fefferman Guy; Elisha Levin Aleksey
Original assignee: Landa Labs 2012 Ltd
Current assignee: Landa Labs 2012 Ltd
Priority date: 2023-02-27
Filing date: 2023-02-27
Publication date: 2024-08-28
Also published as: GB2627839A; GB202302788D0; GB202316241D0

Abstract

A method for manufacturing flakes, comprising: a) providing a liquid stock consisting of at least one material dispersed or dissolved in a liquid; b) applying the liquid stock on a movable surface 210’ to form a thin film of liquid; c) removing at least part of the liquid from the thin film of liquid so as to form a thin coat of precipitated material(s); and e) urging the first movable surface into contact with a countersurface 220 with a nip 200 therebetween, so as to obtain flakes having a thickness of at most 20 µm, and an aspect ratio between the longest planar dimension of the flakes and their thickness of at least 5:1. Flakes made thereby and an apparatus for producing the same are also disclosed, the apparatus comprising a feeder for a liquid stock, a support structure for at least two rotatable cylinders, a compression mechanism for urging the surfaces of two adjacent cylinders together, a drive mechanism for the cylinders, and a collector for flakes.

Description

METHOD AND APPARATUS FOR PREPARING FLAKES

FIELD

The present disclosure relates to a method for manufacturing flakes out of materials disposed in a liquid and to an apparatus enabling the implementation of the method.

BACKGROUND

Modifying the morphology of materials has long been known to prospectively affect their properties or behaviours in a variety of ways too numerous to list extensively. One of the many properties that can be affected by changing the dimensions and shapes of a material, and inter alia their specific surface area, is their solubility in any particular liquid. Increasing the specific surface area of a material, and for instance their rate of dissolution, has far reaching application in a wide range of fields, including for example, the agricultural industry, the cosmetic industry, the manufacturing industry, the water treatment industry, the fire suppression industry, the pharmaceutical industry, and the food industry, to name a few.

As the latter fields, which ultimately involve ingestion of products by living subjects, can be more readily appreciated, no pun intended, the benefits of the following disclosure shall be illustrated inter cilia with respect to constituents of such goods.

Flavor perception is a complex process that involves smell, taste, and chemical sensations (e.g., pungency, astringency, irritation, etc.). Regarding taste, it is perceived through dedicated taste receptors located within the taste buds found on the tongue, the side of the mouth, the soft palate, the cheeks, the back of the throat and even in the oesophagus. The five main tastes perceivable are sweet, sour, salt, bitter and umami, as can be detected when eating, for instance, sugar, vinegar, salt, caffeine and monosodium glutamate, respectively. The compounds or compositions that may induce or elicit taste perception of one or more of the taste categories or other taste sensation are referred to as tastants. Tastants may be added to food products to improve the overall taste. The tastants need to be in solution to be perceived as a taste, which is one of the reasons that animals salivate. Once the taste molecules are dissolved in the saliva, they can suitably contact the taste receptor nerve located within each taste bud and stimulate it so as to accordingly transmit the perception of the relevant taste to the brain.

While the importance of taste is not limited to food consumed by humans and may similarly impact the compliance of other animals to ingest for instance medications, it may be easier to discuss the present problems in this context. Considering for example salt (sodium chloride) and sugar (e.g., glucose, fructose, sucrose, lactose, etc.), both are significant ingredients of food stuff that we may eat or drink, their relatively high presence being even notified as a health concern on packaging in view of their long-term effects. Too much salt in the diet, through its sodium part, can lead to high blood pressure, heart disease, and stroke, among other ailments. Too much sugar can also lead to weight gain, eye, kidney or nerve damages, and diabetes, if the insulin endogenously produced by the subjects is insufficient to eliminate such excess sugar. On the other hand, too little of them is also undesired, insufficient salt levels leading for instance to weakness, nausea, or muscle cramps; and insufficient sugar levels (e.g., hypoglycemia) being capable of causing headaches, dizziness or confusion. If salt or sugar levels are too low for a prolonged period of time, the medical consequences may worsen and be lethal, if untreated. For some individuals, having access to food products with reduced amounts of some tastants is medically warranted.

In recent years, the food industry has made efforts to reduce the contents of salt and sugar in their products, such decrease in their amounts being sometimes compensated by the addition of substances potentiating their taste effect. Additional approaches include replacing these leading tastants by substances providing a similar taste while being deemed less deleterious to the health; or manufacturing them as hollow structures (e.g., spheres or cubes) or as thin coatings over an edible core, the increased surface provided by such methods enhancing the perceived taste. The simple grinding of tastants into particles of smaller sizes which could achieve an increase in specific surface area, a better adhesion to dry food products, and an enhanced taste perception was ruled out at as a viable solution, this approach yielding a new problem of flowability, tiny particles having a higher tendency to stick one to the other into chunky aggregates, this clogging and clumping leading to difficult handling, transportation and storage. But wellbeing is not the only reason a consumer, and more so the food industry, would want the presence of a tastant to be relatively reduced. Cost may also prompt such a choice.

There remains a need to modify the morphology of materials so as to improve at least one of their properties as can be desired for their future intended uses. In the context of ingested goods such a morphology-derived improvement may be exemplified by maintaining the satisfactory organoleptic sensation associated with the tastants, while reducing their presence.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments of the disclosure will now be described further, by way of example, with reference to the accompanying figures, where like reference numerals or characters (or last digits thereof) indicate corresponding or like components. The description, together with the figures, makes apparent to a person having ordinary skill in the art how some embodiments of the disclosure may be practiced. The figures are for the purpose of illustrative discussion and no attempt is made to show structural details of an embodiment in more detail than is necessary for a fundamental understanding of the disclosure. For the sake of clarity and convenience of presentation, some objects depicted in the figures are not necessarily shown to scale.

In the Figures: Figure 1 depicts a flowchart of a method for preparing (e.g., tastant) flakes according to embodiments of the present teachings.

Figures 2-7 each schematically illustrates a nip or series of nips, as may be used according to one embodiment of a method or an apparatus of the present teachings.

Figures 8A and 8B are pictures captured by scanning electron microscopy (SEM) having furthermore focused ion beam (FIB) capacity. Figure 8A shows a tastant before being processed by a method or using an apparatus according to the present teachings; whereas Figure 8B show the same tastant after being processed thereby. In this particular embodiment, the tastant is fed as a dry powder.

Figures 9A and 9B are pictures similarly captured by SEM-FIB microscopy. Figure 9A shows a tastant before being processed by a method or using an apparatus according to the present teachings; whereas Figure 9B show the same tastant after being processed thereby. In this particular embodiment, the tastant is fed as a paste consisting of a dry powder dispersed in a viscous medium.

Figures 10A and 10B are pictures similarly captured by SEM-FIB microscopy. Figure 10A shows a tastant before being processed by a method or using an apparatus according to the present teachings; whereas Figure 10B show the same tastant after being processed thereby. In this particular embodiment, the tastant is fed as a solution.

Figures 11A and 11B are pictures similarly captured by SEM-FIB microscopy. Figure 11A, which is identical to Figure 10A, shows a tastant before being processed by a method or using an apparatus according to the present teachings; whereas Figure 11B show the same tastant after being processed thereby. In this particular embodiment, the tastant is fed as a dispersion.

Figures 12A and 12B are pictures similarly captured by SEM-FIB microscopy. Figure 12A, which is identical to Figures 10A and 11A, shows a tastant before being processed by a method or using an apparatus according to the present teachings; whereas Figure 12B show the same tastant after being processed thereby. In this particular embodiment, the material is fed as a dispersion in a liquid in which it is not soluble.

Figures 13A and 13B are pictures similarly captured by SEM-FIB microscopy. Figure 13A shows a water-soluble material before being processed by a method or using an apparatus according to the present teachings; whereas Figure 13B show the same material after being processed thereby. In this particular embodiment, the material, which is not a tastant, is fed as a solution.

Figures 14A and 14B are pictures similarly captured by SEM-FIB microscopy. Figure 14A shows a water-insoluble material before being processed by a method or using an apparatus according to the present teachings; whereas Figure 14B show the same material after being processed thereby. In this particular embodiment, the material is fed as a dispersion.

Figures 15A and 15B are pictures similarly captured by SEM-FIB microscopy. Figure 15A shows a water-insoluble material before being processed by a method or using an apparatus according to the present teachings; whereas Figure 15B show the same material after being processed thereby. In this particular embodiment, the material is fed as a solution in a non-aqueous solvent.

DETAILED DESCRIPTION

In order to address some of the drawbacks of the art, the present invention seeks to modify the morphology of materials, such as tastants, so as to obtain flakes thereof. The methods and apparatuses designed for this purpose can be accordingly referred to as "flaking" processes and devices.

While the disclosed invention is not limited to tastants and may similarly apply to additional water-soluble or water-insoluble materials, which may elicit different morphology-derived advantages once flaked as herein described, for simplicity of illustration the present technology will be mainly exemplified with these particular types of materials. Hence, reference in the following for brevity to tastant(s) should be understood to refer more generally to any materials that may be similarly processed as herein demonstrated in a non-limitative manner.

Before explaining at least some embodiments in detail, some general introductions shall be provided.

Water-soluble materials can dissolve (e.g., form a clear solution) in water. A water-soluble material would at least dissolve in water at a concentration of 10 g/1 (in other words, at 1 wt.% or more), the water-soluble materials used in the present compositions being in some embodiments water-soluble by 2 wt.% or more, 4 wt.% or more, 6 wt.% or more, 8 wt.% or more, or 10 wt.% or more. Water-solubility is typically assessed at room temperature (between 20°C and 25°C), but a material suitable for the present method may alternatively, or additionally, be water-soluble at an elevated temperature (e.g., at which thinning and/or confinement may be performed). While solubility is often referring to water, similar rules may apply to the solubility of a material in any other solvent of interest and similar rules may apply. Solubility (or lack thereof) in any liquid can be assessed by the naked eye, a composition in which a material is soluble at a particular concentration being typically clear, while an insoluble material would form a turbid dispersion.

While many tastants are water-soluble materials, this is not essential for the performance of the present teachings and some ingredients known to provide a taste and including water-insoluble constituents (e.g., cacao, coffee) can also be flaked. For avoidance of a doubt, the present method is suited for both water-soluble and water-insoluble materials, regardless of their intended use. Moreover, the materials can be either dissolved in a single phase in a liquid (forming a solution) or suspended as solids in a different phase (forming a suspension or a dispersion) for their successful flaking.

For illustration, the materials, even if water-soluble, can be flaked at a concentration higher than their solubility in an aqueous liquid carrier being considered or can be dispersed in a liquid carrier other than pure water in which they might be insoluble (i.e., dissolve at less than 1 wt.%). In such cases, the water-soluble materials would be suspended rather than dissolved.

Alternatively, the materials, even if water-insoluble, can be flaked in a liquid carrier other than pure water in which they might be soluble (i.e., dissolve at more than 1 wt.%). In such cases, the water-insoluble materials would be dissolved rather than suspended.

The present teachings may not necessarily modify the absolute water-solubility of a material (e.g., transform a water-insoluble material into a water-soluble version of the same) but may nevertheless sufficiently improve the rate of dissolution to obtain a detectable upgrade of practical significance. For illustration, a quasi-insoluble material (e.g., dissolving in water at less than 100 ppm) may not turn highly soluble, but can progress thanks to the present teachings to become sparingly soluble. Moreover, the solubility might not be the property sought to be modified by the change in morphology of the material.

In some embodiments, the rate of dissolution of the flakes made from the flaked material is at least 20% higher than the dissolution rate of the unflaked counterpart, at least 30% higher, at least 40% higher, at least 50% higher, or at least 60% higher. The improvement in the rate of dissolution between an unflaked and a flaked version of a same material can also be in some embodiments of 2-fold or more, 3-fold or more, 4-fold or more, 5-fold or more, or 6-fold or more. In particular embodiments, the improvement in rate of dissolution conveyed by the implementation of the present method can be measured in order of magnitude and be of 10-fold or more.

While the materials have been characterized by their solubility in water (or lack thereof), this need not be the only liquid of relevance to the assessment of the improved rate of dissolution. For illustration, if the material is to be used in a manufacturing process in which the intended liquid of the reaction is an alcohol, then the improvement in dissolution rate can be assessed in said alcohol. The rate of dissolution of a material can be assessed by routine experimentation using standard methods, known to the skilled persons.

Due to their size and morphology, traditionally prepared tastants only partially dissolve in the mouth during consumption so that a major portion of the tastant is swallowed without contributing to the perceived taste of the product. Without wishing to be bound by any particular theory, it is believed that the morphology according to the present teachings facilitates the dissolution of the tastants, accordingly increasing the taste that would be perceived, as compared to a same amount of a less soluble counterpart of the tastant. In other words, for a similar taste, flavor intensity and duration of perception of the taste, a tastant having a morphology according to the present teachings would be required in a lesser amount than the same tastant having a conventional morphology.

While tastants can be conventionally provided in a variety of forms, shapes and dimensions, they are traditionally available as small granules which can have a grain size of 25 mm, or even up to about 10 mm if coarse and/or flaky, the grains being typically in the range of 1-2 mm, some tastants being available as fine powders of 0.2-1 mm, or even less for particular applications (e.g., sugar powder). Some tastants, for which reduced consumption is sufficiently critical to afford substantive research, have been developed to even be in the micrometer (pm) range, generally having at least one dimension greater than 20 pm, greater than 30 pm, or greater than 40 pm. Many of them have remained of anecdotic interest, since such exceedingly small particles do not generally readily flow and cannot be applied using conventionally available equipment. Materials, other than tastants can exist as much larger pellets in the range of centimeters (cm), or as small granules in the range of a few millimeters (mm) which can have a grain size of up to 10 mm. Yet, for the implementation of the method, it might be advantageous to use elements of reduced sizes, such as of the tastants.

The dimensions of particles (e.g., before or after being processed as herein disclosed) may be estimated by scanning electron microscope (SEM), transmission electron microscope (TEM) focused ion beam (FIB), by confocal laser scanning microscopy techniques, and/or by light microscopy. For instance, light microscopy can be used for particles of several microns or down to estimated dimensions of about 200 nm, scanning electron microscopy may be used for assessment of planar dimensions for particles having dimensions of less than 200 nm, while thickness or length of particles can be determined by focused ion beam FIB technique. Such dimensions can be assessed, for instance, by image analysis of at least one instrumental field of view obtained by suitable microscopic technique and magnification, and the microscopic measurements being repeated on a number of particles to gain statistical significance, the representative particles being in one or more fields of view. Certain microscopes incorporate image analyser able to readily provide metrics of relevance to the population of particles captured in the relevant field of view. Depending on the microscopy technique, the magnification and the size of the particles under investigation, a field of view may include at least 5 particles, at least 10 particles, or at least 20 particles; and optionally, at most 200 particles, or at most 100 particles, or at most 50 particles. In some embodiments, a field of view includes a number of particles within a range of 5 to 200, 10 to 100 or 20 to 50. In some embodiments, two or more distinct fields of view are being considered to reach the number of particles deemed sufficient to reasonably represent the population. As used herein, an average dimension reflects the mean value of such dimension as estimated on at least 10 particles, at least 20 particles, or at least 50 particles. Selecting a representative particle, or a group of representative particles, that may characterize with sufficient accuracy a population (e.g., by diameter, longest dimension, thickness, aspect ratio and like characterizing measures of the particles, or average values thereof) can be within the skills of a trained operator.

According to one aspect of the disclosure, there is provided a material (e.g., a tastant) having the shape of a thin flake, which can be referred to herein as a flake or a tastant flake. The tastant flake can be defined by its thickness (or average thickness across its planar dimension; 1) and by its longest dimension (L) in the plane, and further characterized by a dimensionless aspect ratio between the two (Asp=L/t). In clear contrast with conventional tastants, the present flakes have at least their thickness being in the low micrometer range (e.g., being thinner than 20 pm, 10 pm, or 5 gm), the thickness of the tastant flakes being optionally in the submicron range (e.g., being thinner than 1 pm), or in the nanometer (nm) range (e.g., being thinner than 200 nm, 150 nm or 100 nm). Flakes of tastant having an average thickness between 1 and 10 pm can also be referred to as tastant micro flakes, flakes of tastant having an average thickness between 0.2 and 1 pm can also be referred to as tastant sub-micro flakes, and flakes of tastant having an average thickness smaller than 0.2 pm can also be referred to as tastant nano flakes.

In some embodiments, the average thickness t of the (e.g., tastant) flakes is at most 20 pm, 18 pm, 16 pm, 14 pm, 12 pm, or 10 pm. In some embodiments, the average thickness of the tastant flakes is at most 9 pm, 8 pm, 7 pm, 6 pm, 5 gm, 4 pm, 3 pm, or 2 pm. In some embodiments, the average thickness of the tastant flakes is at most 1 pm, 0.9 pm, 0.8 pm, 0.7 pm, 0.6 pm, 0.5 pm, 0.4 pm, or 0.3 pm.

In some embodiments, the average thickness t of the (e.g., tastant) flakes is at least 50 nm, at least 100 nm, at least 150 nm, or at least 200 nm.

In some embodiments, the average thickness of the (e.g., tastant) flakes t is between 50 nm and 20 pm, between 100 nm and 18 pm, between 100 nm and 16 pm, between 150 nm and 14 pm, between 150 nm and 12 pm, between 200 nm and 10 pm, between 200 nm and 5 pm, 20 between 100 nm and 4 gm, between 100 nm and 2 pm, or between 100 nm and 1 gm.

In some embodiments, the longest planar dimension of the water-soluble material (e.g., tastant) flakes L is on average at most 500 pm, at most 400 pm, at most 300 pm, at most 200 pm, at most 100 pm, or at most 50 pm.

In some embodiments, the longest planar dimension of the (e.g., tastant) flakes L is on average at least 5 pm, at least 7.5 pm, at least 10 gm, at least 12.5 pm, or at least 15 pm.

In some embodiments, the longest planar dimension of the (e.g., tastant) flakes L is on average between 5 pm and 500 pm, between 7.5 pm and 300 pm, between 10 pm and 200 pm, or between 10 pm and 100 pm.

In some embodiments, the aspect ratio between the longest planar dimension of (e.g., tastant) flakes and their thickness (Asp= Lit) is on average at least 5, at least 10, at least 15, at least 20, or at least 25.

In some embodiments, the aspect ratio between the longest planar dimension of the (e.g., tastant) flakes and their thickness (Asp= Lit) is on average at most 200, at most 150, at most 125, at most 100, at most 75, or at most 50.

In some embodiments, the aspect ratio between the longest planar dimension of the (e.g., tastant) flakes and their thickness (Asp= Lit) is on average between 5 and 150, between 10 and 100, between 10 and 50, between 50 and 150, or between 20 and 75.

Advantageously, tastant flakes having the afore-mentioned dimensions are expected to display good blendability in the food products, good adherence to food surfaces (and in turn more uniform coverage of the surface) and less dusting problems than their conventional counterparts.

As the tastant flakes have a higher specific surface area than their standard counterparts they can dissolve faster, providing a more intense taste for a same amount of tastant or a same taste with a lower amount, allowing to reduce the contents of the tastant in the food product. Having a higher specific surface area may not only accelerate the rate of dissolution of any specific material in any particular liquid, but may also increase any other desirable interactions between molecules. Taking chemical reactions as an example, and materials serving as catalysts in such reactions, catalysts having a relatively higher surface area are expected to stimulate more swiftly the rate of the chemical reaction they usually promote than their counterparts having a relatively smaller surface area.

The tastant flakes are capable of imparting a sweet, salty, sour, bitter or umami taste and can be made of any tastant known or being developed to provide such tastes, or of their combinations. In some embodiments the tastant flakes comprise one or more of acetic acid, citric acid, lactic acid, malic acid, ascorbic acid, tartaric acid, succinic acid, hydrochloric acid, phosphoric acid, sulphuric acid, sucrose, arabinose, ribose, xylose, glucose, galactose, mannose, fructose, lactose, maltose, raffinose, stachyose, trehalose, glycerol, erythritol arabitol, xylitol, sorbitol, mannitol, lactitol, malitol, corn syrups, low molecular weight maltodextrins, bitter peptides, amino acids, alkaloids, amides, thioureas, polyphenols, sodium bicarbonate, monosodium glutamate, di sodium 5' -inosate, and di sodium 5' -guanyl ate, sodium chloride, iodized sodium chloride, calcium chloride, potassium chloride, iodized potassium chloride, or mixtures thereof As the present approach does not rely on the presence of taste modulating compounds to alter the perception of the taste provided by a tastant, the tastant flakes (which can consist of a pure compound or a blend of natural tastants) are devoid of aftertaste. This may also increase compliance with customers seeking clean alternatives as close as possible to their natural source of tastants. This would certainly be the case when the tastant flakes are made of a single material (e.g., salt).

But tastants are only provided as examples and additional materials can be flaked as herein taught. Suitable materials can be water-soluble or water-insoluble, organic (e.g., plastics or other non-polar compounds) or inorganic (e.g., ceramics, minerals, metal-based, etc.) and be found in a variety of chemical families.

Water-soluble materials other than tastants, or used in context other than providing a taste or otherwise improving an ingested product, include, for instance, sodium chloride (Nadi), which is commonly known as table salt as used in food seasoning, can also be used as a deicing agent, a reagent or a catalyst in the manufacturing of chemicals. A non-limiting list of water-soluble materials include for illustration: Ammonium nitrate (NI-T4NO3) which can be used on fertilizers, as an explosive, and in the production of nitric acid; Calcium carbonate (CaCO3) which can be used as a dietary supplement in human and animal food, as an antacid both in medicine and more agricultural/industrial settings, as a filler in the production of adhesives, sealants, paints, coatings, papers and plastics, and in the manufacturing of cement and concrete; Calcium chloride (CaC12) which in addition to its uses in food processing can be used as a deicing agent and in the production of cement and concrete; Copper sulfate (CuSO4) which can be used as a algaecide, bactericide, fungicide, herbicide, molluscicide and root killer, in addition to being a catalyst; Ferric chloride (FeCl3) which can be used to treat sewage, industrial waste, to purify water, as an etching agent for engraving circuit boards, and in the manufacture of other chemicals; Magnesium sulfate (MgSO4) which can be used in agriculture as a fertilizer, in medicine as a laxative, in the production of paper and textiles, and as a catalyst; Manganese sulfate (MnSO4) which can be used as a fertilizer and as livestock supplement where soils are deficient in manganese, then in some glazes, varnishes, ceramics, and fungicides; Potassium chloride (KC1) which can be used as a fertilizer and in the manufacturing of potassium hydroxide (KOH) itself used in the production of soaps and detergents; Potassium hydroxide which in addition to its uses as a pH adjuster in food processing can be used in the manufacturing of soap and detergents and in the production of biodiesel; Potassium iodide (ICI) which can be used as dietary supplement, as a medication for treating hyperthyroidism, in radiation emergencies, and for protecting the thyroid gland when certain types of radiopharmaceuticals are used, and as a catalyst; Potassium nitrate (KNOB) which in addition to its uses in food preservation can be used in fertilizers and in the manufacturing of gunpowder; Sodium bicarbonate (NaHCO3) which in addition to its uses in food processing can be used in medicine as antacid, or combined with organic acids such as citric and tartaric acid to provide the effervescent effect to active pharmaceutical ingredients, and in fire extinguishers; Sodium hydroxide (NaOH) which can be used in the manufacturing of soap and detergents, as a drain cleaner and in the production of paper; and Zinc chloride (ZnC12) which can be used in dry cells as an electrolyte, as a catalyst, a condensing agent, a dehydrating agent, a deodorant, a disinfectant, or a wood preservative.

Water-insoluble materials which may benefit from the present method, generally, but there are exceptions readily ascertainable, include carbonates, phosphates, sulfides, and oxides.

Taking, for illustration, materials including a metal such as calcium, then Calcium carbonate (CaCO3), Calcium phosphate (Ca3(PO4)2), Calcium sulfate (CaSO4), Bone meal ((Ca(PO4)2)3CaF2), Rock phosphate (Ca3(PO4)2CaF2), and other such phosphate minerals can be cited as water-insoluble materials of widespread uses. Other common water-insoluble materials include Barium carbonate (BaCO3), Barium sulfate (BaSO4), Copper carbonate (CuCO3), Iron oxide (Fe2O3), Lead chromate (PbCrO4), Lead chloride (PbC12), Lead sulfate (PbSO4), Silicon dioxide (SiO2), Silver chloride (AgCI), Magnesium hydroxide (Mg(OH)2), Magnesium stearate (Mg(Ci8H3502)2) and Zinc oxide (ZnO).

As readily appreciated from the foregoing list of exemplary materials, many are salts which exist in various forms of hydrates and/or crystals, some forms having different roles, but all supporting that a wide variety of industries may benefit from the present teachings and all forms being encompassed as materials adapted to the present flaking method.

Regardless of the types of materials constituting the flakes, they can be considered as made of a pure material, if this material constitutes at least 95% of the flakes by weight, the degree of purity as assessed by weight contents being advantageously of at least 96 wt.%, at least 97 wt.%, at least 98 wt %, at least 99 wt.%, or at least 99.5 wt %. The purity of the material (or of a blend of materials) in the flakes can be determined by any analytical method adapted to measure a definite property (e.g., elemental composition, physico-chemical property, etc.) of the material(s) under consideration.

In some embodiments, the (e.g., tastant) flakes have a specific surface area of at least 0.01 m2/g, at least 0.05 m2/g, at least 0.1 m2/g, at least 0.2 m2/g, at least 0.3 m2/g, at least 0.4 m2/g, or at least 0.5 m2/g. Generally, the tastant flakes have a specific surface area not exceeding 10 m2/g, their specific surface area being usually of at most 8 m2/g, at most 6 m2/g, at most 4 m2/g, or at most 2 m2/g. For reference, tastants having a granular shape which could be approximated to a sphere, and having an average diameter of 50 um, might have a specific surface area of no more than about 0.2 ni2/48, for a tastant having a same density. The surface area of a material can be routinely determined by any suitable method, such as by nitrogen sorption as can be analyzed by the Brunauer-Emmett-Teller (BET) or Langmuir procedures, in any adequate instrument, and the specific surface area calculated based on the weight of the measured sample.

The (e.g., tastant) flakes may additionally, or alternatively, be characterized in that their bulk density (ps), also referred to as their apparent density, i.e. the ratio of the mass to the bulk volume (VB) of an untapped (hence, including interparticulate void volume) powder sample, is relatively lower than the bulk density of their standard counterparts. In other words, for a same volume of tastant particles (e.g., a tablespoon) the weight of tastant would be relatively reduced when the tastant is flaked as herein disclosed. If the taste provided to the food product is not compromised by the reduced bulk density, this allows to diminish the weight contents of the tastant accordingly. However, if a taste to be provided by the tastant flakes is affected by the reduction in bulk density, the reduction in weight of tastant being added to the food product would no longer be analogous to the decrease in bulk density, as additional volume of tastant would probably be added to compensate for the initial "weight loss" induced taste impairment.

In some embodiments, the bulk density of the (e.g., tastant) flakes is at least 20% lower than the bulk density of the standard counterpart, at least 30% lower, at least 40% lower, or at least 50% lower. Taking salt for illustration, standard granulated salt typically has a bulk density of about 1.25 g/cm3, in which case the reduced bulk densities of tastant flakes would be of at most 1.00 g/cm3 (80% of 1.25 g/cm3), at most 0.88 g/cm3, at most 0.75 g/cm3, or at most 0.62 g/cm3. Bulk density of tastant flakes can be even lower, if desired, such as being of at most 0.50 g/cm3, at most 0.40 g/cm3, or at most 0.30 g/cm3, but it generally needs not being lower than 1% or even 5% of the original bulk density of the conventional tastant. Thus, in some embodiments, the bulk density of the tastant flakes is between 0.01 g/cm3 and 1.00 g/cm3, between 0.01 g/cm3 and 0.80 g/cm3, between 0.05 g/cm3 and 0.50 g/cm3, between 0.10 g/cm3 and 0.75 g/cm3, between 0.10 g/cm3 and 0.70 g/cm3, between 0.05 g/cm3 and 0.65 g/cm3, or between 0.20 g/cm3 and 0.62 g/cm3. The apparent bulk density of a particulated matter can be assessed by routine experimentation using standard methods, such as described in ASTM B527.

When the (e.g., tastant) flakes are to be mixed with other dry powders (e.g., other flakes) for their intended use, it may be advantageous for all powders being mixed to have a relatively similar bulk density so as to reduce the separation of the powders and maintain a homogenous mix. The bulk density would be considered relatively similar, if the bulk density of an individual component of the mixture would be within 20% deviation from the bulk density of the mixture.

The (e.g., tastant) flakes may additionally, or alternatively, be characterized in that their tap density (pr) is relatively lower than the tap density of their standard counterparts. In contrast with the bulk density, the measurement of the tap density involves tapping of the sample to reduce interparticulate voids and assess the packing ability of the powder. For a defined mass of powder, the bulk density is calculated by measuring the bulk volume Vie occupied by the mass of the powder whereas the tap density is calculated by measuring the tapped VT volume typically shrank by the rearrangement of the powder during the application of tapping. Usually, unless the powder is perfectly free flowing, the tap density of a powder is higher than its bulk density but the differences between the two values depend on the intrinsic properties of the particles (e.g., size, shape, porosity, etc.), on the particle size distribution (e.g., homogeneity, ability to segregate, etc.) and on inter particle interact ons as may also result from their environment (e.g., moisture, temperature, etc.).

In some embodiments, the tap density of the tastant flakes is at least 20% lower than the tap density of the standard counterpart, at least 30% lower, at least 40% lower, or at least 50% lower, but it generally needs not being lower than 5% of the original tap density of the conventional tastant. Taking salt for illustration, standard granulated salt typically has a tapped density of about 1.45 g/cm3, in which case the reduced tapped densities of tastant flakes would be of at most 1.16 g/cm3 (80% of 1.45 g/cm3), at most 1.02 g/cm3, at most 0.87 g/cm3, or at most 0.73 g/cm3. Tapped density of tastant flakes can be even lower, if desired, such as being of at most 0.50 g/cm3, at most 0.40 g/cm3, or at most 0.30 g/cm3, but it generally needs not being lower than 5% of the original tap density of the conventional tastant. Thus, in some embodiments, the tap density of the tastant flakes is between 0.07 g/cm3 and 1.02 g/cm3, between 0.07 g/cm3 and 0.87 g/cm3, between 0.10 g/cm3 and 0.73 g/cm3, between 0.07 g/cm3 and 0.50 g/cm3, or between 0.20 g/cm3 and 0.73 g/cm3.

A relatively low bulk and/or tap density, as can be displayed by the present tastant flakes, is deemed advantageous, in particular when the tastant is to be applied to the surface of dry snack foods, such as crisps or nuts. For such foods the conventionally applied tastants generally suffer from relatively high lost during processing due to their relatively poor adhesion and/or their relatively high tendency to detach and fall off the food product by the time it is to be consumed. Such phenomenon leads to unnecessary wastage of the tastant.

While having a tastant shaped as a flake may by itself increase the likelihood of sufficient contact to promote adhesion during the application of the tastant to the food product, as compared to a more granular form of the tastant, this is but a first requirement. The tastant flakes should also remain on the product, during the remaining processing steps, and any subsequent handling of the food product such as its packaging, transport and storage. It has been reported that tastants having a relatively lower bulk density are less prone to detach from the food surface than tastants having a relatively higher bulk density. This can be explained in part by the fact that particles having a lower bulk density and accordingly a smaller mass are less affected by gravity than particles having a higher bulk density / larger mass, thus such tastant flakes could better maintain their adhesion to the food product until it is ingested.

In some embodiments, the (e.g., tastant) flakes may be made of a water-soluble or water-insoluble material having a crystalline structure. In such a case, the flakes may, for some materials, be additionally, or alternatively, characterized by a particular crystallographic structure as detectable by X-ray diffraction (XRD), the XRD detectable structure being selected from a group consisting of a position of a diffraction peak, a relative intensity of a diffraction peak at a particular position, a ratio between any two diffraction peaks at two particular positions, a diffraction peak width, a crystallite size, a microstrain value and a dislocation density at any particular diffraction peak or over the spectrum of scanning, and like parameters indicative of a crystallographic structure.

In some embodiments, at least one of the aforesaid crystallographic parameters as measurable by XRD or other suitable method on the (e.g., tastant) flakes diverge by at least 20% as compared to the same parameter as measured in the unflaked crystalline material. In some cases, the value of the parameter measured in the flakes can be diverging by being at least 20% lower or at least 20% higher than the same parameter as measured in the standardly grown / prepared crystal. In some embodiments, at least one of these crystallographic parameters as measurable on the flakes diverge by at least 30%, by at least 40%, or by at least 50%, as compared to a corresponding parameter in a reference standard unflaked crystal. For some crystallographic parameters, the difference between a measurement made in the flakes as compared to a measurement made in the relevant reference crystal can even be of at least 2-fold, at least 3-fold, or at least 4-fold.

For illustration, crystallite size and microstrain values, which can be indicative of relatively high compression perceived during the crystal growth and the confinement of the precipitated material(s) by passage(s) through the nip(s) can be respectively at least 2-fold smaller or 2-fold larger in tastant flakes made of salt, as compared to standard salt.

An XRD structure detectable in the original unflaked material (e.g., tastant) before being processed according to the present method and/or using an apparatus as herein taught, can be referred to as an XRD detectable first structure, whereas a corresponding structure detectable in the (e.g., tastant) flakes following their preparation may be referred to as an XRD detectable second structure. The structures in the unflaked original material and the flaked version of the same are deemed corresponding if relating to a similar parameter as analyzed at about a similar position or along a similar spectrum span, since understandingly a modification in the crystallographic structure of a crystalline material as may occur in some embodiments, may in itself cause minor shifts in the diffraction peaks. Thus, corresponding structures need not be identical but the parameters being asserted should in essence be of a same kind.

While in the foregoing the (e.g., tastant) flakes have been characterized by one parameter at a time, such as by i) their thickness, ii) their length, iii) their aspect ratio, iv) their specific surface area, v) their bulk density, their tap density, or any ratios between the two densities, or vi) any crystallographic specification adapted to a material, if crystalline, the skilled persons can readily appreciate that flakes, as can be produced by the present method, may be characterized by any combination of two or more of these parameters. For illustration, a tastant flake may have both a bulk density and a crystallographic behavior as herein disclosed. In some embodiments, the tastant flakes displaying the aforesaid characteristic parameters are furthermore made of a pure tastant (e.g., constituting more than 95 wt.% of the flakes).

For example, tastant flakes according to the present teachings can be a) made of a pure salt, such as containing more than 95 wt.% of sodium chloride for instance; b) having a relatively low bulk density not exceeding 0.50 g/cm3, being optionally of at most 0.45 g/cm3, at most 0.40 g/cm3, at most 0.35 g/cm3, at most 0.30 g/cm3, at most 0.25 g/cm3, at most 0.20 g/cm3, at most 0.15 g/cm3, or at most 0.10 g/cm3; and c) having an XRD detectable structure being at least one of i) a microstrain value of at least 0.050%, at least 0.075%, at least 0.100%, at least 0.125%, at least 0.150%, or at least 0.175%; and fi) a crystallite size of at most 1000 Angstroms (A), at most 750 A, at most 625 A, or at most 500 A. According to another aspect of the disclosure, there is provided a method for manufacturing flakes (e.g., tastant flakes), the method comprising: a) providing a material (e.g., tastant); b) feeding the material i) in particulated form, either dry or dispersed, or ii) dissolved in a liquid to a nip formed between two rotating cylinders urged into contact one with the other; c) collecting a thinned (e.g., precipitated) coat of the material downstream of the nip; and d) repeating steps b) and c) so as to obtain (e.g., tastant) flakes having an average thickness of at most 20 i.un, at most 10 pm, at most 5 pm, or at most 1 pm and an aspect ratio between the longest planar dimension of the (e.g., tastant) flakes and their thickness being on average of at least 5, at least 10, or at least 15.

In some embodiments, the recycling of the thinned material providing the flakes of step d) is to the same nip to which the material was first fed. In other embodiments, the recycling can be to one or more nips different from the nip of first feeding, which may be called the first nip. While in case of multiple nips, each nip may be constituted of a pair of cylinders having no contact with any of the cylinders of another nip, it may be preferred in some embodiments to have the multiple nips sharing common cylinders. The rotating cylinders of each nip, and a forliori of different nips, need not be the same. While for efficiency they typically have a similar axial length, they may have different diameters, and/or be made of different matters, and/or be coated with different substances, and/or be heated or cooled to different temperatures, etc. In one embodiment, the material (e.g., tastant) is provided in dry particulated form. While this method is appropriate for any tastant existing in dry form (e.g., plant spices derived from roots, stems, bark, leaves, flowers, or seeds) it is particularly indicated for tastants which cannot be dispersed or dissolved in a medium from which they might be efficiently isolated with relative ease. This "dry method" typically enables an at least 5-fold thinning of the tastant from an initial dimension (e.g., diameter, edge, thickness) to its final thickness, following an ultimate recycling of the thinned tastant. This method is generally suitable for the preparation of micro flakes.

In one embodiment, the material (e.g., tastant) is provided as a relatively viscous paste (e.g., having a dynamic viscosity of 1,000 milliPascal-seconds (mPa.$) or more at room temperature circa 23°C). The viscosity of the paste can be achieved by dispersing a relatively high quantity of tastant in a relatively low quantity of liquid, and/or by using a liquid relatively viscous in itself The dispersing medium should preferably be compatible with the tastant (e.g., not affecting its taste), and if necessary or desired, it should be separatable therefrom. The dispersing medium, which can itself be relatively viscous, can be selected in accordance with a future use of the tastant flakes. For instance, the tastant can be cacao and the viscous medium cacao butter (both water-insoluble) or sugar and molasses (both water-soluble), at least one of the rotating cylinders being optionally heated or cooled to maintain a desired viscosity to the paste. This example in non-limiting and the dispersing (e.g., viscous) medium need not be of a similar source or type as the tastant. This "paste method" typically enables an at least 10-fold thinning of the tastant from an initial dimension (before forming the paste) to its final thickness, following an ultimate recycling of the thinned tastant. This method is generally suitable for the preparation of micro flakes and sub-micro flakes.

A dispersing medium adapted to form with the material a relatively viscous paste can be an intrinsically viscous product, such as honey for a tastant, or be prepared by increasing the viscosity of a non-viscous liquid. Such increased viscosity allowing the paste to display a dynamic viscosity of at least 1,000 mPa.s at room temperature can be achieved by using a relatively high amount of material (e.g., tastant) and/or by including a thickening agent in the dispersing medium. If the material to be flaked is intended to provide a taste or be used in a product to be ingested, the thickening agent should preferably be tasteless by itself and advantageously, but not necessarily, approved for food consumption, to the extent that residual amounts are not eliminated from the surface of the tastant flakes. Such thickening agents, which can be natural or synthetic, are known and can, for instance, be selected from a group comprising alginic acid (E400), sodium alginate (E401), potassium alginate (E402), ammonium alginate (E403), calcium alginate (E404), propylene glycol alginate (E405), agar (E406), carrageenan (E407), furcelleran (E408), locust bean gum (E410), oat gum (E411), guar gum (E412), tragacanth (E413), gum Arabic (E414), xanthan gum (E415), karaya gum (E416), tara gum (E417), gellan gum (E418), pectin (E440), gelatin (E441), cellulose (E460), methyl cellulose (E461), ethyl cellulose (E462), hydroxypropyl cellulose (E463), hydroxy-propyl-methyl cellulose (E464), methyl-ethyl cellulose (E465), carboxymethyl cellulose (E466), natural or modified starches (E1400 series), and combinations thereof.

In one embodiment, the material (e.g., tastant) is provided dispersed or dissolved in a liquid relatively non-viscous having a dynamic viscosity of less than 1,000 mPa.s, less than 100 mPa.s, or less than 10 mPa.s or less at room temperature (e.g., water). The liquid should be compatible with the material (e.g., not affecting its taste, if a tastant), and if necessary or desired, it should be separatable therefrom. Tastants suitable for such method are typically, but not necessarily, solvable in the liquid, even if fed at a concentration higher than their limit of solubility, the tastants being accordingly dispersed rather than fully dissolved in the liquid. This "liquid method" typically enables an at least 15-fold thinning of the tastant from an initial dimension (before mixing in the liquid) to its final thickness, following an ultimate recycling of the thinned tastant. This method is generally suitable for the preparation of sub-micro flakes and nano flakes.

As mentioned, it is stressed that the selection of liquid carriers, additives thereto, matters of which parts of the apparatus are made or coated with, with respect to any material to be flaked by the present method and/or with the apparatus herein described, is guided by principles of compatibility. The materials should be chemically compatible with one another. Fundamentally, a material or a chemical composition is compatible with another (or inert with respect thereto, if so desired) if it does not prevent its activity or does not reduce it to an extent that would significantly affect the intended purpose. For instance, a liquid carrier would not be compatible if, among other things, affecting the taste of a material being a tastant intended for ingestion, or affecting the potency or reactivity of materials intended for manufacturing processes. The materials should also be physically compatible with one another. For illustration, the liquid carrier should preferably be sufficiently volatile at a temperature not affecting the material(s) to be flaked. Thus, the materials should also be compatible with the manufacturing method and its operating conditions and vice versa. For illustration, the liquid stock in which the materials to be flaked are dissolved or dispersed should not be corrosive to the surfaces to be applied thereto or the surfaces should be inert with respect to the stock and the flakes to be produced therefrom. Such general considerations shall not be further detailed herein, as known to persons skilled in the field of chemical manufacturing.

However, in some embodiments, the liquid can be selected to intentionally trigger a reaction with the material being flaked. In such case, the chemical composition of the material before and after its flaking may differ. Hence, the term "flakes made from the material(s)" encompass both flakes having retained the original chemical composition of the material treated by the present flaking method, as well as flakes including a modified version of the material. For illustration, if calcium carbonate is flaked in neutral water, the flakes obtained therefrom will consist of calcium carbonate. However, if calcium carbonate is flaked in acetic acid, the flakes obtained therefrom may consist of calcium acetate, the reaction between the carbonate salt and the acetic acid also producing water and carbon dioxide.

Regardless of the form in which the material (e.g., tastant) is fed to one or both surfaces forming any particular nip (e.g., in dry form, in a paste, or dissolved or dispersed in a liquid), its application can be continuous or intermittent.

Considering in a particular aspect the latter manufacturing of flakes from a material fed dispersed or dissolved in a non-viscous liquid, in one embodiment the method comprises: a) providing at least one material (e.g., tastant) dispersed or dissolved in a liquid so as to form a liquid (e.g., tastant(s)) stock; b) applying the liquid (e.g., tastant(s)) stock to a surface so as to form a thin film of liquid (e.g., tastant(s)) stock; c) removing at least a part of the liquid from the thin film of liquid (e.g., tastant(s)) stock so as to form a thin coat of precipitated tastant(s), the thin coat optionally having a thickness of no more than 100 pm; and d) confining the thin coat of precipitated water-soluble material(s) (e.g., tastant(s)), so as to obtain (e.g., tastant(s)) flakes having a thickness of 20 pm or less and an average aspect ratio between their longest planar dimension and their thickness of at least 5:1.

While in theory the liquid stock can be applied at any initial thickness, a relatively thicker film being expected to require a longer duration of process than a relatively thinner one under otherwise similar conditions, in some embodiments, the thin film of the liquid stock has an initial thickness of 250 pm or less, the material(s) being preferably homogenously di spersed or dissolved (or both) in the liquid at the time of their application. A liquid stock in which the material to be flaked is dissolved can also be referred to as a stock solution. A liquid stock in which the material to be flaked is dispersed can also be referred to as a stock dispersion.

For similar reasons, while in theory the liquid stock can be applied at any initial concentration of the material, it may be advantageous to use relatively concentrated ones which are expected to require a shorter duration of process than a relatively dilute stock under otherwise similar conditions. Understandingly, a relatively high proportion of a material in a liquid may affect its viscosity. It is therefore stressed that while the liquid carrier used to form the liquid stock can by itself be non-viscous (e.g., having a dynamic viscosity of less than 1,000 mPa.$), the liquid stock can on the contrary be slightly viscous. Thus, while the liquid stock may also be non-viscous, in some embodiments, the liquid stock can have a dynamic viscosity of up to 100,000 mPa.s, up to 75,000 mPa.s, up to 50,000 mPa.s, up to 25,000 mPa.s, up to 10,000 mPa.s, or up to 5,000 mPa.s, as measured at room temperature.

In some embodiments, the surface to which the liquid stock is applied is wettable by said liquid stock, the liquid being able to spread over the surface.

In some embodiments, the thin film of the (e.g., tastant(s) liquid stock is obtained by intermittently or continuously applying the liquid stock to the (e.g., wettable) surface, the surface being movable, and inter alia by passing the applied stock through a nip formed by urging into contact the movable surface and a counter surface one against the other. The applicator of the liquid stock of material(s) and the surface are typically in relative motion one with respect to the other. As used herein, the terms "tastant(s) stock", "liquid stock", "tastant(s) liquid stock", or even "stock" can be interchangeably used to refer to the liquid containing the dispersed or dissolved material(s) (e.g., tastant(s)). The liquid carrier of the stock can be constituted of one or more fluids (and additives therein, if desired), the liquid carrier being relatively non-viscous (i.e., having a dynamic viscosity of less than 1,000 mPa.s at room temperature).

In some embodiments, the confinement of the thin coat of precipitated material(s) (e.g., tastant(s)) is obtained by passing the thin coat through a same or at least one different nip than the one used inter edict to level the liquid stock into a thin liquid film, so as to obtain (e.g., tastant(s)) flakes having a thickness of at most 20 pm, at most 10 p.m, at most 5 p.m, or at most 1 um and an aspect ratio between the longest planar dimension of the (e.g., tastant) flakes and their thickness being on average of at least 5:1, at least 10:1, or at least 15:1 (also referred to for brevity as at least 5, at least 10, or at least 15).

As appreciated from the above exemplary illustration, the confinement of the thin liquid film and of the coat of material(s) resulting therefrom by one or more passages through one or more nips may also provide a "crushing" step transforming the material(s) precipitated in the coat into flakes. The crushing step may not necessarily require a dedicated action and can naturally result from the previously described steps. In other words, crushing encompass any inherent or intended event which include the consolidation of the precipitated materials into a thin coat of relative uniformity, the detachment of the thin coat from the movable surface, and the break-down of the relatively dry thin coat into individual flakes.

For the sake of efficiency, the material (e.g., tastant) can be provided with dimensions facilitating its dispersion or dissolution in the liquid, and for example can be grinded to have a largest dimension not exceeding 5 mm. When the material is solvable in the liquid carrier of the stock, the process can be alternatively, or additionally, accelerated by using a saturated or near saturated solution. A saturated solution is a solution in which there is so much solute that if there was any more, it would not dissolve and would for instance precipitate out of solution as a solid. The maximum amount of any material (e.g., tastant) in a saturated solution thereof depends inter alio on the material, on its initial specific surface area, on the liquid in which it is dissolved, on the temperature of the solution, on pressure applied thereto and any other conditions (e.g., stirring) maintaining a homogenous concentration of the material in the solution. Therefore, a solution that can be saturated, for instance, at a relatively elevated temperature can be supersaturated (containing a higher than expected amount of soluble material) at a relatively lower temperature. Near saturated solutions comprise less than the maximum amount of material that may dissolve under the conditions set for the preparation of the solution. Such amounts (e.g., between 70% and 90% of the maximum amount) may suffice to render the solution saturated under different conditions to which the near saturated solution may be subjected during the process for preparing the flakes.

In other words, while a solution can be prepared to be near saturated, saturated, or supersaturated upon completion of its preparation, such classification may evolve during the process. For illustration, a near saturated solution may become a saturated solution as liquid is removed therefrom and may even turn into a dispersion once the material (e.g., tastant) starts to precipitate out of solution (e.g., by crystallization of the material). In this context, a dispersion of a material being otherwise solvable in the liquid, indicates that the material is present at a concentration higher than tolerable for the formation of a supersaturated solution. Alternatively, the material may be dispersed in a liquid in which it is not solvable. For illustration, a material soluble in water need not be soluble in alcohol.

As used herein, "precipitate", "precipitation", and grammatical variants are not used to exclusively refer to a process resulting in the formation of a substance permanently insoluble in the liquid (e.g., solution or dispersion) from which it precipitated out. On the contrary, these terms are meant to also include any processes resulting in the formation of a solid substance separable from a liquid, the substance being converted in such process to an insoluble form, even if reversibly. Crystallization is a particular kind of precipitation process in which the structure of the substance rendered solid by loss of solubility becomes organized. A particular material (e.g., tastant) being a crystalline material may have a number of polymorphs, all being herein encompassed.

In some embodiments, the dispersion or the dissolution of the material (e.g., tastant) in the liquid is performed at a temperature above room temperature, this temperature not exceeding the boiling temperature of the liquid. Considering water as an exemplary liquid, the dispersing or dissolving step can be performed at a temperature of at least 30°C, at least 40°C or at least 50°C; and at most 95°C, at most 90°C or at most 85°C. If the liquid is an alcohol or contains enough alcohol or any other material having a boiling point lower than water, then the upper limits of the afore-said ranges should be reduced according to the relative proportions of such volatile fluids in the liquid, the dispersing or dissolving step being performed for illustration at a temperature between 30°C and 75°C. The temperature not to be exceeded during this step should also consider the heat resistance of the material (or the heat resistance of the most sensitive material, if more than one), and in the case of a tastant should preferably be lower than a temperature at which the taste of the tastant would be detectably impaired, as can be determined by organoleptic testing.

Regardless of the temperature at which the dispersing or dissolving step can be performed, it may also be performed at a pressure other than ambient atmospheric pressure.

Furthermore, and regardless of temperature and/or pressure conditions, the dispersing or dissolving step can be performed under ongoing agitation of the liquid while dispersing or dissolving the tastant therein and/or while maintaining the tastant liquid stock homogeneous for the formation of the continuous film (i.e., during its application to a surface). Regardless of the conditions elected for the preparation of the liquid stock, it may be applied on the movable surface at a temperature above ambient temperature. This should be the case in particular if the surface is itself being heated at a same or different temperature above ambient temperature.

In some embodiments the removal of at least part of the liquid out of the (e.g., tastant) liquid stock forming a thin continuous film on the surface is expeditious. Without wishing to be bound by any particular theory, it is believed that, if sufficiently rapid, the liquid removal (e.g., evaporation) can take place while the material (e.g., tastant) is still relatively homogeneously dispersed or dissolved in the thin film. Quick removal of the liquid at such a stage enables the formation of a relatively homogenous coat of precipitated material (e.g., tastant), which in turn may facilitate the crushing of the coat into flakes having a relatively uniform thickness during the even confinement of the coat. A liquid film, a dry coat, a population of flakes or of nano flakes have a relatively uniform thickness if the ratio between their respective largest and smallest thickness, or their respective largest and smallest average thicknesses, is 10 or less, 8 or less, 6 or less, 5 or less, 4 or less, 3 or less, or 2 or less.

Advantageously, the rate of liquid removal in the present method is such that the formation of a coat of precipitated material (e.g., tastant) can take place in less than 1 minute from a time the thin film of (e.g., tastant) liquid stock is formed. In some embodiments, the liquid removal step takes 50 seconds or less, 40 seconds or less, or 30 seconds or less. If the method of liquid removal alternatively or further includes heating the surface upon which the liquid stock was applied to form a thin film, the liquid removal step can also be referred to as an evaporation step. In some particular embodiments, the liquid removal or evaporation step takes 20 seconds or less, 15 seconds or less, or 10 seconds or less. The liquid removal or evaporation step can be performed while blowing or aspiring away at least part of the liquid being removed or its vapors.

While any liquid could be used based on its ability to satisfactorily dissolve or disperse the tastant and on its relative ease of removal for the sake of process efficiency, it may be advantageous to select liquids also approved for animal (e.g., human) consumption. Such liquids are known and need not be detailed but for illustration can be selected from a group consisting of water, alcohols, fatty alcohols, glycerol (also called glycerine), propylene glycol, and combinations thereof When the water-soluble material is not a tastant, or to be used for animal ingestion (e.g., dietary supplement. medicine, eic.), the liquid may additionally be selected from a wider range of fluids, which nevertheless may also take into account the intended use of the flaked material. For illustration, if the flakes are to be used in a manufacturing process, the liquid can be compatible with the process (e.g., not inhibiting an intended reaction).

Advantageously, but not necessarily, the liquid, whether pure or blended, should enable the dissolution of the material (e.g., tastant) to a concentration of at least 1 g per 100 g of the liquid (1 wt.%), or of at least 5 g of tastant per 100 g of the liquid (5 wt.%), at least 10 g of tastant per 100 g of the liquid (10 wt.%), at least 20 g of tastant per 100 g of the liquid (20 wt.%), as measurable at room temperature. To the extent that the flakes may retain residual liquid on their outer surface, the liquid should preferably be selected to be compatible to the intended use of the material, for instance, for tastants, not exceeding a content that would be deemed toxic for consumption. In other words, the liquid should preferably be Generally Recognized as Safe (GRAS), food-grade, and/or labelled with any other like denomination indicating its suitability for oral consumption when the material is intended for ingestion.

Alternatively, the liquid, whether pure or blended, should only enable the dispersion of the material (e.g., tastant), in other words the material dissolving at a concentration of less than 1 g per 100 g of the dispersing liquid (< 1 wt.%).

In some embodiments, the movable surface (e.g., wettable by the liquid stock (e.g., solution or dispersion)) is the surface of a rotating cylinder. In such a case, the liquid removal step configured to remove at least a part of the dissolving or dispersing liquid can preferably take place during no more than 60 cycles of the rotating cylinder, the number of cycles necessary to enable sufficient removal of at least a part of the liquid depending on the initial concentration of the material (e.g., tastant) in the liquid, the rotational speed of the cylinder, the temperature of the surface of the cylinder, and like factors. In some embodiments, the liquid removal or evaporation step takes 50 cycles or less, 40 cycles or less, 30 cycles or less, 20 cycles or less, or 10 cycles or less. Preferably, the liquid removal or evaporation step should take 8 cycles or less, 6 cycles or less, 4 cycles or less, or 2 cycles or less, and ideally 1 cycle or less.

For avoidance of a doubt, it is stressed that the removal of the liquid from a liquid film of stock need not be complete for material(s) (e.g., tastant(s)) to start precipitating. Consequently, the crushing of a coat of precipitated material(s) into flakes can also initiate before complete liquid removal following one or more cycles of confinement. In other words, the removal of a first part of the liquid may cause the precipitation of a first part of precipitated tastants, and while this first part would be crushed the removal of a second part of the liquid could cause the precipitation of a second part of precipitated tastants, and so on. Thus, while the steps of liquid stock application, partial liquid removal till partial precipitation, and confinement leading to partial crushing of the precipitated material(s) are sequentially correct, a subsequent step does not require the full completion of a previous step to initiate, and some steps may coexist each for a different part of the film of liquid stock, precipitated coat, and confined (and crushed) coat. Based on the same rational of a process allowing for concomitant coexistence of various phases, it can be appreciated that if all steps were to be ideally carried out in a single cycle through the nip, then different sections of the movable surface (e.g., rotatable cylinder) may display relative enrichment in products of the various phases.

When the surface upon which the film of (e.g., tastant) liquid stock is turning into a thin coat of precipitated material (e.g., tastant) is the outer surface of a rotatable cylinder, confinement of the foregoing and crushing of the coat into flakes can be performed at a nip between the rotating cylinder and a counter surface urged into contact one with the other, by advancing the thin coat of precipitated material(s) towards the nip. The counter surface can be static, in which case, the surface coated with the precipitated material(s) and the counter surface are in relative motion. The counter surface may alternatively be movable and can for instance be a second rotating cylinder. In such case, the two surfaces may enter the nip at a same or a different speed, the two cylinders being either rotating in a same direction or in opposite directions.

While the nip is being described as providing for the confinement of the thin film of liquid stock and of the coat of precipitated material (e.g., tastant), and optionally for the crushing of the coat into flakes, this may not be its sole role in the present method. Without wishing to be bound by any particular theory, the pressure applied at the nip upon the film of liquid stock is believed to contribute to the removal of at least part of the liquid from the film, even at ambient temperature, without further heating of the surface of the cylinder. Regardless of the mechanisms of action that may be relevant to the restricted volumes of liquid stock, thinning film thereof, coat of precipitated material, and/or flakes crushed therefrom, that can be confined once or more times by the nip, it is believed that controlling the nip (e.g., by its operational parameters, such as speed of rotation, temperature, contact pressure, etc.) can inter alia dictate some characteristics of the (e.g., tastant) flakes being manufactured therethrough (e.g., size, morphology, etc.) and/or of the process efficacy.

In some embodiments, the pressure applied during at least one of: a) the formation of the thin film of (e.g., tastant) liquid stock, b) the at least partial removal of the liquid and c) the confinement and/or crushing of the thin coat of precipitated material(s), is at least 10 MPa, at least 50 MPa, or at least 100 MPa. Typically, the pressure applied at an ideal line of contact between surfaces involved in one or more nips in the present method does not exceed 1,500 MPa, being sometimes no higher than 1,250 MPa, or no higher than 1,000 MPa. If more than one nip is employed in the present method, a pressure applied at a first nip need not be the same as a pressure applied at another nip. This may be the case if the series of nips is formed radially around a common central cylinder, each externally rotating cylinder being urged into contact therewith at a different pressure. In some embodiments, the pressure applied each nip can independently be between 10 MPa and 1,500 MPa, between 50 MPa and 1,250 MPa, or between 100 MPa and 1,000 MPa. The afore-said pressures are the maximum Hertzian contact pressure values calculated based on the forces that can be applied to urge the various surfaces into contact.

The force / pressure applied to urge surfaces of the method / apparatus into contact for the formation of at least one nip need not be constant during the performance of any of the steps herein disclosed. Taking for clarity of illustration a material (e.g., tastant) being fed as a dry powder to a single nip, the thinning of the powder into flakes requiring more than one passage through the nip, the force applied by the compression mechanism and the pressure perceived at the nip may be gradually increased until reaching a peak or plateau value in the aforesaid ranges of suitable pressures. Alternatively, the force applied by the compression mechanism could be constant, but the pressure perceived at different nips in a series of nip compressed by the same mechanism could be distinct. For illustration, considering a series of nips linearly aligned and formed by a series of rotatable cylinders having a gradually decreasing diameter, the pressure perceived at a nip between relatively smaller cylinders would be higher that the pressure perceived at a nip between relatively smaller cylinders, so that for a same force the pressure would be increasing as the diameter is decreasing.

Interestingly, a same compression mechanism can be used to simultaneously apply a force on two or more series of rotating cylinders / nips, each series forming an independent module capable of producing same or different (e.g., tastant) flakes, as herein taught. For illustration, a same compression mechanism can be applying a force on a first series of rotating cylinders forming a first series of nips (e.g., to produce flakes of a first material), and on a second series of rotating cylinders forming a second series of nips (e.g., to produce flakes of a second material). The first and second series are physically separated one from the other and can be arranged in parallel or serially one with the other.

Such configurations, enabling the simultaneous preparation of flakes of two or more different materials on separate series of nips, can be advantageous when preparing flaked materials to be mixed one with the other. In such a case, the second material need not to provide any taste by itself if the first material is a tastant intended for that purpose. For illustration, a first material to be flaked on a first series of nip can be sodium bicarbonate, its flaking according to the present teachings being expected to reduce the presence of sodium that might be required for this agent to be sufficiently effective in a food product. As sodium bicarbonate may require, for products deprived of natural acids, the addition of an acidifying agent to react therewith for the release of carbon dioxide which ultimately leavens the product when entrapped in the batter, it can be suitable to flake an appropriate second material at the same time. For example, acetic acid (CH3CO2H; E260), acid calcium phosphate (ACP; Ca(H2PO4)2; E341), acidic sodium aluminium phosphate (SALP; E541), citric acid (HOC(CO2H)(CH2CO2H)2; E330), tartaric acid (C4H606; E334), or sodium acid pyrophosphate (SAPP; Na2H2P207; E450), to name a few weak acids which exist in crystal forms, can be flaked on a second series of nip the mixture of the two materials enabling the preparation of baking powders, or other food products (e.g., flours) typically including such agents. Similarly, when none of the materials is a tastant, they may be two or more materials adapted for a same manufacturing process, the prospective "contamination" of flakes of a first material with flakes of a second (or third etc.) material having no deleterious effect on the intended manufacturing process.

In view of the relatively high pressures that can be applied at a nip, the rotating cylinder(s) and counter surface are advantageously made of materials having sufficient hardness, or any other property providing mechanical resistance, adapted to resist such pressures without significant deformation and/or wear. The rotating cylinder(s) and counter surface may be made of or coated with a metal (e.g., stainless steel), a ceramic (e.g., tungsten carbide (WC)), or a polymer (e.g., Kevlar®), so has to have on their outer surfaces contacting one another a Vickers hardness of at least 50 HV, at least 100 HV, at least 150 HV, or at least 200 HV. While the hardness of the materials need not be limited, it typically does not exceed 10,000 HV (e.g., if coated with a diamond like carbon (DLC) film), being often less than 5,000 HV, less than 3,500 HV, less than 2,000 HV, or less than 1,500 HV. The hardness desired for any surface may decrease as the pressure to be applied thereto is relatively reduced.

The hardness of the cylinders or their outer surface depends on a) the exact composition of each cylinder and coating, if present, and b) whether the bulk material was further treated (e.g., annealed, cold worked, hardened, heat treated or tempered), and in the affirmative to what extent (e.g., stainless steel can be tempered to be 1/16, 'A, 'A '/2, 3/4, or Full Hard). While the relative resilience of the rotating cylinders is expressed above in terms of their hardness, a person skilled in materials and their physical properties can readily "translate" such requirements in other terms, such as strength, yield point and the like, all such alternative, or additional, parameters being likewise selected to avoid or minimize deformation and/or wear of the surface of the cylinders under the operational conditions of the method or apparatus.

In some embodiments, the rotating cylinder(s) and counter surface are not only made of sufficiently hard and resilient materials, but additionally have a desirable surface topography (e.g., being smooth or textured, whether or not randomly). In some embodiments, the surfaces to be pressed one against the other are relatively smooth. In such case, they may have a surface roughness (Ra) of 500 nm or less, 400 nm or less, 300 nm or less, 200 nm or less, or 100 nm or less. While perfectly smooth surface may ideally display a null average surface roughness, typically Ra is greater than 20 nm.

The temperature of the rotating cylinder(s) and counter surface can be adjusted as desired, by using any suitable internal or external heating or cooling device. The temperature of the rotating cylinder(s) and counter surface can be selected according to principles similar to those described for the preparation of the (e.g., tastant) liquid stock. However, following the application of the liquid stock, it is no longer essential to avoid exceeding the boiling temperature of the liquid.

The heating may take different forms depending on the temperature to be reached and can be by conduction, convection and/or radiation. Conduction can be achieved by positioning heating elements underneath a surface or liquid to be heated; or by circulating a hot liquid (e.g., heated oil or water) in pipes, chambers or jackets suitably located for that effect. Heating by convection can be achieved by blowing a hot gas (typically air) towards the surface to be heated. Heating by radiation can be achieved with microwaves, if in a suitable chamber, but more typically infrared lamps directed to radiate towards the relevant surface or material.

As appreciated by a skilled person, the rate at which the liquid (e.g., tastant(s)) stock is applied to the movable (e.g., wettable) surface depends inter aka on the surface tension of the liquid stock and the surface energy of the surface, the desired thickness of the thin film, the rate of removal (e.g., evaporation) of the liquid under operating temperature and pressure conditions, the speed of the surface at the nip, and like factors. The flow rate, or the metering of doses intermittently applied, can be empirically determined and adapted as desirable.

The thin film can be formed by running the surface to be coated trough a bath of the (e.g., tastant) liquid stock, by dripping or spraying the liquid stock on the surface through one or more nozzles disposed in parallel to the line of contact of the nip / the axial length of the rotatable cylinder, the nozzles being for instance arranged across the width of the movable surface, by providing the liquid stock upstream of a device configured to level it (e.g., a doctor blade, an air knife, a squeegee, etc.) or by any other method adapted to form a liquid film of minute thickness on a surface. As can be appreciated, in some embodiments, the liquid need not be applied as a thin film upstream of a nip, the nip itself serving to level an excess volume of liquid stock forming an initial, optionally transient, upstream pool into a downstream thin film.

As readily appreciated, for a predetermined concentration of material (e.g., tastant) in the liquid, a relatively thinner film of (e.g., tastant) liquid stock enables a relatively faster removal of the liquid, or at least a part thereof, than a relatively thicker film, all other conditions of the method being similar. In some embodiments, the thin film has an initial thickness at the time of application to the surface (prior to any significant removal of liquid) of 250 gm or less, 125 pm or less, 70 pm or less, or 35 pm or less. Typically, the thin film is applied to have an initial thickness of at least 250 nm, at least 500 nm, at least 750 nm, or at least 1 pm.

The above values refer to an initial thickness, as the present method is intended to remove parts of the liquid over time, so that the thickness of the (e.g., tastant) liquid stock gradually diminishes until the material precipitates into a thin coat, first partially then totally upon complete removal of the liquid. The thickness of the thin coat of precipitating materials may also diminish over time and confinement. As appreciated "complete removal" of the liquid as deemed obtained at the end of the flaking process does not mean that the resulting thin coat of precipitated and confined material (e.g., tastant), nor the flakes to be crushed therefrom, would be totally devoid of liquid which could remain in the "drying" coat or adsorbed on the flake surfaces in relatively minute amounts. Any residual amount of liquid in the thin coat of precipitated material (e.g., tastant) allowing for a commercially significant crushing of the precipitated material into flakes could be tolerated. In some embodiments, the at least partial removal of liquid (e.g., partial evaporation) would enable the production of a crushed thin coat and/or (e.g., tastant) flakes having a liquid content of 10 wt.% or less, as can be determined by weight loss under conditions adapted to substantially fully dry the flakes. In some embodiments, the flakes contain less than 9 wt.%, less than 8 wt.%, less than 7 wt%, less than 6 wt%, less than 5 wt.%, less than 4 wt.%, less than 3 wt.%, or less than 2 wt.% of liquid per weight of the flakes. In other embodiments, the liquid content is deemed insignificant (or the flakes are deemed substantially dry) when the liquid content is of 1 wt.% or less, 0.8 wt.% or less, 0.6 wt.% or less, 0.4 wt.% or less, 0.2 wt.% or less, 0.1 wt% or less, or 0.05 wt. ;/o or less, by weight of the (e.g., tastant) flakes.

While the process for preparing (e.g., tastant) flakes by the present method could ideally be continuous, generally when relying on more than one nip, it may alternatively be performed in an alternating "Stop and Go" manner. In such case, a dose of liquid is applied, and only once this first dose has been transformed into flakes, a second dose is applied, and so one and so forth. When a number of nips are involved in the process, a second dose can be applied before the flakes are collected at the last nip. It is therefore believed that a higher number of nips may shorten the time between application of separated doses or may even render the process continuous.

The (e.g., tastant) flakes can be naturally collected into a collector, the flakes spontaneously detaching from the thin coat disposed on the surface as it is confined (and/or crushed) and being funneled by gravitation to the collector. The flakes can be additionally, or alternatively, actively collected, using for instance a blade, a propelled jet of gas (e.g., air), or any other mean suitable to detach the flakes from the thin coat of precipitated material (e.g., tastant). Typically, flakes having spontaneously detached from the rotating surface upon which they were formed are relatively larger and/or thicker than flakes actively detached with the assistance of a detaching device.

The (e.g., tastant) flakes obtained by such method may not be sufficiently thinned after a single passage through the nip to form micro flakes, sub-micro flakes or nano flakes of desired dimensions. In such a case, the flaked product collected from the nip of first confinement (and/or crushing) can be advanced towards one or more additional nips until the collected product displays the properties desired for the flakes. It is believed that passing the flakes through additional nips, once most of the liquid has been removed or evaporated after cyclic passage through the first nip, can assist removing residual liquid that might be absorbed on the surface of the flakes.

Alternatively, or additionally, the (e.g., tastant) flakes obtained by such method may contain a residual amount of liquid that may be incompatible with intended use and/or storage stability. Regardless of the reason for its desirable elimination, the method may further include a step dedicated to the removal of residual liquid, if any. For illustration, the flakes may be dried.

As the (e.g., tastant) flakes prepared according to the methods herein disclosed have a relatively high specific surface area as compared to their conventional unflaked counterparts, some may display an increased tendency to absorb ambient moisture. This phenomenon may lead to caking of the flakes, impeding their flow-ability and making their transport, handling, storage, and application more difficult. In such a case, the flakes may be treated with additives capable of inhibiting caking, and the present method may further comprise a step to this effect.

In some embodiments, the method may further comprise sorting of the (e.g., tastant) flakes according to size so as to increase the size uniformity of each sub-population sorted thereby. By way of example, the flakes may be sieved through meshes of desired aperture size.

A population of flakes having relatively uniform particle dimensions is expected to provide for a relatively more consistent effect, as may be required when standardized performance are expected from the flakes or the products incorporating them.

All optional steps that may be performed following the collection of the flakes, not being limited to the ones above-exemplified, can be referred to as post-processing steps, or post-flaking steps. Devices or sub-systems enabling their performance in an apparatus for manufacturing flakes accordingly, can be referred to as post-processing stations, or post-flaking stations.

While the method has been described with respect to a single material (e.g., tastant), it can similarly be used to prepare flakes of two or more materials. For illustration, if each material is a crystal, the method can be used to achieve their co-crystallization, the confinement and/or crushing steps enabling the preparation of flakes of a mixture of the materials (e.g., tastants).

The terms "material(s) or "tastant(s)" can be used herein to indicate that one or more materials or tastants could be used in the step, device or product being described.

A flake prepared as herein described, regardless of the number of distinct materials (e.g., tastants) being used for their preparation, generally contains more than one individual element of precipitated material(s), for illustration more than a single crystal of a tastant precipitating with a crystallographic structure. A flake is usually constituted of several such elements typically forming a continuous mosaic of precipitated material(s) (e.g., a plurality of salt or sugar crystals, if the material is a crystalline tastant). Advantageously, in some embodiments, the mosaic of precipitated material(s) appears in the resulting flake as substantially merged / essentially devoid of voids between the various elements forming the flake.

Some embodiments of the present method and its various steps are depicted in Figure 1 in which a box having a dashed contour indicates an optional step.

In a first step S01, one or more materials (e.g., tastants) to be manufactured as flakes are provided. Typically, the material(s) are provided as dry powders of various shapes and dimensions. If the material(s) is/are provided as a paste or a liquid, the method may start from step S03 to obtain a concentration of material(s) and/or a viscosity of liquid stock as desired or may even start from step SO4 if the material(s) have a desirable concentration (e.g., adapted to form at least a near saturated solution) and/or if the liquid stock has a desirable viscosity (e.g., not exceeding 1,000 mPa.s at the temperature of dispersion, dissolution or application).

If the materials (e.g., tastants) are provided as dry powders and one of the materials has a relatively large initial size, for instance having at least one dimension larger than 5 mm, the material can be size reduced by any suitable method to have preferably all dimensions not exceeding 5 mm. For illustration, this second step SO2 can consist of optionally grinding the at least one material provided in S01.

In a third step 503, the at least one material (e.g., tastant) (which may have been optionally size reduced to any desirable grain size in the low millimeter range (e.g., between 0.5 and 5 mm)) is dissolved or dispersed into a liquid (the number of phases in the liquid stock depending on relative amounts and/or on the nature of the liquid and the capacity of the material to dissolve therein). This step can be performed under agitation, heat, and/or pressure, as previously described and adapted to the liquid stock to be obtained.

In a fourth step SO4, the (e.g., tastant(s)) liquid stock is applied to a movable surface (which may optionally be wettable by the liquid stock). Typically, the applicator of the liquid stock and the surface to be coated therewith as a thin liquid film are in relative movement. The applied liquid can be leveled to form a thin film using a dedicated leveling device setting a desirable initial thickness or/and by displacing the applied liquid (or liquid film having a first thickness) towards a nip formed between the movable surface and a counter surface.

The nip between the two surfaces is formed by urging one against another in a step illustrated as SO5 in Figure L The nip can be a single nip, or a series of nips as shall be further detailed with reference to Figures 2 to 7.

While the optional heating of at least one of the movable surface and counter surface is illustrated as S06 apparently following SO5, this is not the sole possible sequence of events, and the optional heating of the surfaces (or one of them) may alternatively, or additionally take place before the application of the liquid stock (before 504) and/or before the liquid stock reaches the nip (before SO5) In a seventh step 507, at least a part of the liquid is removed from the thin film of (e.g., tastant(s)) liquid stock. While ideally, the liquid should be removed rapidly enough to ensure the formation of a thin coat of precipitated material(s) (e.g., tastant(s)) in a single passage through a single nip, to permit continuous application of the liquid stock, this is not essential. The method can be alternatively continuously carried out by running the thinning film of liquid stock through a series of nips, the thin coat of precipitated material(s) generally forming after the last or the penultimate nip. The method can also be carried out in an alternative mode with respect to the application of the liquid stock, the thinning film of liquid stock passing more than one time through a same nip or through a series of nips, the thin coat of precipitated material(s) generally forming after the last or the penultimate passage through the (last or penultimate) nip. The progressive removal of the liquid leads to the precipitation of the material(s), which can also be an ongoing event. Considering for illustration a tastant made of a crystalline material, the precipitation of a first part of the tastants can result in the formation of initial crystals constituting in turn nucleation centers for tastants subsequently precipitating out of the film of liquid stock.

In an eighth step S08, the thin coat of precipitated material(s) (e.g., tastant(s)) is confined (and/or crushed down to flakes). As for the gradual removal of the liquid, this may occur in one or more passages through a same or different nips. While for simplicity referred to as "confining" or "confinement", this step may achieve several effects that could be synchronous and not necessarily distinguishable, nor all taking place. Advantageously, the confinement, regardless of methods or means to implement it, is believed to achieve a consolidation of the precipitated material(s), the individual elements of precipitant having a relatively high cohesion among themselves and the thin coat being relatively more uniform (e.g., in continuity, in thickness, etc.) than a layer resulting from a "confinement-deprived" precipitation of same materials. Thus, while conventional precipitation could form relatively friable agglomerates of individual precipitated elements, the present confinement of the liquid stock and of the materials precipitated therefrom would initially include an amalgamation in which individual precipitated elements could be considered as merging one with the other. Flakes obtained by the present method may therefore have a relatively low porosity and/or a relatively high transparency. In some embodiments, the (e.g., tastant) flakes have a porosity of at most 30%, at most 25%, at most 20%, or at most 15%. In some embodiments, the flakes have a porosity of at least 1%, at least 2%, or at least 5%.

In a ninth step S09, the (e.g., tastant(s)) flakes can be collected from the last surface upon which the thin coat of precipitated material(s) was disposed. When the method is carried out in a series of nips, the collection can be performed at different nips. If the collected fractions have similar properties (e.g., similar dimensions), the different nips can serve to increase the productivity of the method. If the fractions collected at the different nips have distinct properties (e.g., different dimensions, aspect ratios, etc.), the different nips may serve to sort the flakes produced by the method.

Exemplary different nips of relevance to the present method, and following apparatus, shall be briefly described with reference to their schematic illustrations, as depicted in Figures 2 to 7. For clarity of these non-limiting nip configurations, some devices of the apparatus or enabling the herein disclosed method steps shall not be represented in these figures. The omitted devices might be essential and include, for illustration, a compression mechanism for urging at least one pair of surfaces into contact so as to constitute a nip, or a drive mechanism (e.g., motor, connector, etc.) for driving the rotation of at least one rotatable cylinder. The omitted devices might be optional and include, for illustration, a dosing device capable of periodically providing a desired dose of a liquid stock or a desired continuous flow rate of a liquid stock; a levelling device capable of forming a thin layer of liquid having a desired thickness; a heating device capable of heating the surfaces being coated during the process (the heat being applied from the rear and/or the front side of the surfaces); and a detaching device capable of "scratching away" a thin coat of precipitated material(s) (e.g., tastant(s)) into flakes, such a device being optionally retractable, depending on the nip configuration being elected. Such devices, as well as optional driers, chambers, flake sorters, and like equipment as may be used in the conventional preparation of flakes, are known and need not be detailed herein. Furthermore, all may be arranged on and supported by a suitable structure.

For brevity, principles of operation common to all nip configurations are not necessarily repeated in the following descriptions. For the avoidance of a doubt, while in these figures the various nip configurations are illustrated upon engagement of the surfaces forming the respective nips, in an apparatus including such nip configurations the surfaces can be disengaged to permit maintenance (e.g., cleaning) or replacement of the surfaces when desired. Moreover, while in some illustrated embodiments, the plane including the axes of rotation of the rotating cylinders is depicted with a horizontal orientation, this should not be construed as limiting.

Figure 2 schematically depicts a nip 200 formed by urging a rotating cylinder 210 having an (e.g., wettable) outer surface 210' against a counter surface 220 being planar (and typically, though not necessarily static) and having an outer surface 220' facing the cylinder. In this figure the applicator of the (e.g., tastant(s)) liquid stock is illustrated by arrow 260 and the collector of the (e.g., tastant(s)) flakes is illustrated by vessel 270. While the collector 270 is for simplicity depicted downstream of nip 200, it may alternatively be at any other position along the path followed by the rotating surface 210'. As cylinder 210 may not only rotate around its axis, but also move along the counter surface 220 (up and down in the illustrated figure) the counter surface being static, the collection of the flakes into collector 270 may also take place from a thin coat formed on surface 220'. A similar effect of having the thin coat of precipitated material formed on surface 220' can be achieved conversely by having the axis of rotation of cylinder 210 static, the counter surface 220 being in relative motion therewith (up and down in the illustrated figure) or by having both the axis of rotation of 210 and the counter surface 220 being displaced in the Z-direction in the present illustration, contact between the two surfaces (hence, nip 200) being maintained at all times. The collection of the flakes can result from spontaneous detachment of the flakes, as the thin coat of precipitated material(s) is generated from the removal of the liquid or at least part thereof and is crushed by passage through the nip of confinement, each said step lasting one or more rotations of cylinder 210 and passages through nip 200. The collection of the flakes can also involve a detaching device, which may be controllably operated following the formation of the thin coat of precipitated material(s). For example, detachment can be facilitated by directing, when desired, a jet of gas onto the thin coat or by approaching a suitable mechanical obstacle (e.g., a blade) towards the thin coat, to scrape it away as individual flakes.

Figure 3 schematically depicts a nip 300 formed by urging a first rotating cylinder 310 having an (e.g., wettable) outer surface 310' against a counter surface being a second rotating cylinder 320 having an (e.g., wettable) outer surface 320'. In this figure the two cylinders are rotated in a same (e.g., clockwise) direction generating slippage at the line of contact. The applicator of the (e.g., tastant(s)) liquid stock is illustrated by arrow 360 and the collector of the (e.g., tastant(s)) flakes is illustrated by vessel 370, arbitrarily depicted downstream of nip 300, though it may alternatively be at any other position along the path followed by the rotating surface 310' and advantageously by the rotating surface 320'.

Figure 4 schematically depicts a nip 400 formed by urging a first rotating cylinder 410 having an (e.g., wettable) outer surface 410' against a counter surface being a second rotating cylinder 420 having an (e.g., wettable) outer surface 420'. In this figure, in contrast with Figure 3, the two cylinders are counter-rotated (e.g., one being in a clockwise direction and the other counterclockwise). If the two cylinders have the same speed, slippage at the line of contact can be avoided. The applicator of the (e.g., tastant(s)) liquid stock is illustrated by arrow 460 and the collector of the (e.g., tastant(s)) flakes is illustrated by vessel 470, arbitrarily depicted downstream of nip 400, though it may alternatively be at any other position along the path followed by the rotating surface 410' and advantageously by the rotating surface 420'.

Figure 5 schematically depicts a series of nips 500a, 500b and 500c which are linearly aligned. Nip 500a is formed by urging a first rotating cylinder 510 having an (e.g., wettable) outer surface 510' against a counter surface being a second rotating cylinder 520 having an (e.g., wettable) outer surface 520'. Nip 500b is formed by urging the second rotating cylinder 520 against a counter surface being a third rotating cylinder 530 having an (e.g., wettable) outer surface 530'. Nip 500c is formed by urging the third rotating cylinder 530 against a counter surface being a fourth rotating cylinder 540 having an (e.g., wettable) outer surface 540'. The applicator of the (e.g., tastant(s)) liquid stock is illustrated by arrow 560 and the collector of the (e.g., tastant(s)) flakes is illustrated by vessel 570, arbitrarily depicted downstream of nip 500c, though it may alternatively be at any other position along the path followed by the rotating surfaces 510', 520', 530' and advantageously by the rotating surface 540'. If desired, more than one collector can be used along a series of nips as schematically illustrated for example in Figures 5-7. While a linear alignment of nips has been illustrated in this figure with four cylinders of similar dimensions, each pair of cylinders being counter rotating, this need not be the case. Linear alignment of nips can be achieved with any other number of cylinders being equal or greater than three, the cylinders being same or different, being rotated in same or different direction, and/or at same or different speed.

In some cases, the series of nips (whether or not as schematically illustrated in Figures 57) includes a number of nips sufficiently great under the operating conditions elected for the preparation of the (e.g., tastant) flakes to allow for the presence of more than one applicator capable of feeding (e.g., tastant) liquid stocks on more than one of the outer surfaces of the cylinders constituting the series of nips. The liquid stocks fed by all applicators can be the same and such configuration can be appropriate for continuous application of the liquid stock and collection of the flakes produced therefrom.

Figure 6 schematically depicts a series of nips 600a, 600b, 600c and 600d which are radially aligned towards a common central rotating cylinder 610 having an (e.g., wettable) outer surface 610' (not marked on the figure). Nip 600a is formed by urging against the first rotating cylinder 610 a counter surface being a second rotating cylinder 620 having an (e.g., wettable) outer surface 620' (not marked on the figure). Nip 600b is formed by urging against the first rotating cylinder 610 a counter surface being a third rotating cylinder 630 having an (e.g., wettable) outer surface 630' (not marked on the figure). Nip 600c is formed by urging against the first rotating cylinder 610 a counter surface being a fourth rotating cylinder 640 having an (e.g., wettable) outer surface 640' (not marked on the figure). Nip 600d is formed by urging against the first rotating cylinder 610 a counter surface being a fifth rotating cylinder 650 having an (e.g., wettable) outer surface 650' (not marked on the figure). The applicator of the (e.g., tastant(s)) liquid stock is illustrated by arrow 660 and the collector of the (e.g., tastant(s)) flakes is illustrated by vessel 670, arbitrarily depicted downstream of nip 600c, though it may alternatively be at any other position along the path followed by the rotating surfaces 610', 620', 630', 640', and advantageously by the rotating surface 650'. For instance, collector 670 can be located downstream of nip 600d. While a radial alignment of nips has been illustrated in this figure with four cylinders of similar dimensions dispose on diametrically opposed side of a common central cylinder, each outer cylinder being counter rotating with respect to the central one, this need not be the case Radial alignment of nips can be achieved with any other number of outer cylinders being equal or greater than three, the cylinders being same or different, being rotated in same or different direction, and/or at same or different speed.

Notably, while in Figure 6, rotating cylinders 620, 630, 640 and 650 are disposed to contact the outer surface of a centrally rotating cylinder 610 upon which the liquid stock is applied to be processed by the present method, they can alternatively face the cylindric wall of 610 from the inner side. In such a case, rotating cylinder 610 shall be a hollow cylinder or a drum, and the liquid stock shall be applied on the inner surface of the hollow cylinder. Similarly, the collector 670 would be located within the hollow plenum of 610.

Figure 7 schematically depicts a configuration of a series of nips combining the principles of linear and radial alignment of the nips. The nips between rotating cylinders 710, 720, 730, 740 and 74B form a linear alignment, whereas the nips between 71A, 71B and 710, or 72A, 72B and 720, or 73A, 73B and 730, or 74A, 74B and 740, are deemed to form radial alignments with respect to rotating cylinders 710, 720, 730, and 740, respectively. The applicator of the (e.g., tastant(s)) liquid stock is illustrated by arrow 760 and the collector of the (e.g., tastant(s)) flakes is illustrated by vessel 770, arbitrarily depicted downstream of the nip formed by rotating cylinders 740 and 74C.

In some of the above-described configurations, in particular in those including a series of nips, essential or optional devices which for clarity are not illustrated in the figures may be included more than once. For instance, each rotating cylinder may be independently driven by a different motor. Considering a levelling and/or a detaching device, they need not to be exclusively disposed on the first and the last cylinder, respectively, and they may each be repeatedly disposed along the series of nips. Taking Figure 6 for illustration, a first levelling device could be disposed to face cylinder 610 downstream of the applied liquid stock and upstream of cylinder 620, whereas a second levelling device may be found adjacent cylinder 620, or again adjacent cylinder 610 but downstream of nip 600a. Likewise, a last detaching device may be found to detach flakes from the surface of cylinder 650, but may be preceded by an upstream positioned detaching device which may for illustration be removing the (e.g., tastant) flakes from the surface of cylinder 610 in the section between nips 600c and 600d. An additional collector could be required besides 670, depending on its particular architecture and mode of action, as well as on the exact relative positioning of the detaching devices.

In particular embodiments, regardless of the type of alignment(s) followed by a series of nips (e.g., linear and/or radial), the number of nips and the rotating cylinders forming them are selected to enable a continuous application of (e.g., tastant(s)) liquid stock and collection of (e.g., tastant(s)) flakes upon completion of the process under the operating conditions set therefor.

According to another aspect of the disclosure, there is provided an apparatus for manufacturing flakes of a material disposed in a liquid, the apparatus comprising: a) a feeder adapted to dispense intermittently or continuously a dose or flow rate of a liquid stock including at least one material (e.g., tastant) dissolved or dispersed therein; b) a support structure for supporting two or more rotatable cylinders; c) a compression mechanism for urging the surfaces of each two adjacent cylinders of the two or more rotatable cylinders into a line of contact at a respective nip therebetween; d) a drive mechanism for causing the rotatable cylinders to rotate; and e) a collector for collecting (e.g., tastant) flakes Flom a thin coat of precipitated water-soluble material (e.g., tastant), following a removal of at least a part of a liquid from the liquid stock; wherein the feeder is configured to apply the liquid stock on a first rotatable cylinder of the two or more cylinders and the collector is adapted to collect the flakes after one or more passages of a thin film of the liquid stock through the one or more nips of the two or more rotatable cylinders.

In some embodiments, the apparatus further comprises a levelling device adapted to level the (e.g., tastant) liquid stock into a thin film prior to passage through the nip.

In some embodiments, the apparatus further comprises at least one heating device to heat at least one of the (e.g., tastant) liquid stock to be dispensed by the feeder and any of the surfaces of the two or more rotatable cylinders.

In some embodiments, the apparatus further comprises a detaching device adapted to detach the (e.g., tastant) flakes from the thin coat of precipitated material for their collection by the collector.

In some embodiments, the apparatus further comprises a controller serving to control constantly or periodically at least one of: a-the quantity of liquid stock being dispensed and/or the periodicity or rate of liquid being fed by the feeder; b-the force or pressure applied by the compression mechanism; c-the speed of rotation of at least one of the two or more rotating cylinders; and d-the temperature of the liquid stock and/or the temperature of any surface of the two or more rotating cylinders.

In some embodiments, the outer surface of each of the two or more rotatable cylinders of the apparatus is made of, or coated with, a material wettable by the (e.g., tastant(s)) liquid stock.

In some embodiments, the outer surface of each of the two or more rotatable cylinders of the apparatus is made or, or coated with, a material having an average surface roughness (Ra) of 500 nm or less, 400 nm or less, or 300 nm or less.

In some embodiments, the outer surface of each of the two or more rotatable cylinders of the apparatus is made or, or coated with, a material having a Vickers hardness between 50 HV and 10,000 HV, between 100 HV and 5,000 HV, between 150 ITV and 3,500 ITV, or between 200 HV and 2,000 HV.

According to another aspect of the disclosure, there is provided a product comprising flakes of water-soluble or water-insoluble material(s) as herein disclosed, and/or prepared by the present methods, and/or prepared by using the present apparatus.

According to another aspect of the disclosure, there is provided a food comprising tastant flakes as herein disclosed, and/or prepared by the present methods, and/or prepared by using the present apparatus.

According to another aspect of the disclosure, there is provided a method for improving a food, the method comprising incorporating into the food or beverage flakes as herein disclosed, and/or prepared by the present methods, and/or prepared by using the present apparatus, the flakes optionally being of a tastant. The improvement of the food can be in its taste, its odor, its preservation, its texture, its appearance, or its ease of preparation, to name a few fields in which food improvement can be required.

The food improvement can alternatively, or additionally, be in the prolonged retention or delayed reduction in the properties of the food as displayed when freshly prepared and expected from a consumer using all senses typically involved in the appreciation of a food product. Therefore, in a broader sense, a tastant need not necessarily provide a taste but assist in the perception of a quality of a food product and can be for non-limiting illustration an emulsifier, a thickener, a binder, a gelling agent, a texturizer, a firming agent, a leavening agent, a stabilizer, a preservative agent, an anti-caking agent, an humectant, a pH controlling agent, a color additive, a flavor enhancer, a vitamin, a mineral nutrient, and any like food additive expected to positively affect the characteristics of the food, whether for the sake of its production, processing, treatment, packaging, transportation or storage.

According to another aspect of the disclosure, there is provided a method for reducing the amount of a material in a manufacturing process or in a manufactured product, the method comprising replacing at least a part of the material in said process or product by flakes as herein disclosed, and/or prepared by the present methods, and/or prepared by using the present apparatus.

According to another aspect of the disclosure, there is provided a method for reducing the amount of a tastant adapted to provide a desired taste to a food, the method comprising replacing at least a part of the tastant in said food or beverage by tastant flakes as herein disclosed, and/or prepared by the present methods, and/or prepared by using the present apparatus.

While for brevity the present methods and apparatus have been described as suitable for the preparation of tastant flakes, as relevant to the food industry or any other industry relying on oral administration or use of products inter aka having a taste and/or contributing to a quality of the (e.g., food) product, they may similarly serve for the preparation of flakes intended for any other purpose. The raw material to be flaked need not provide a taste, nor be suited for animal consumption or use, nor be intended for the food industry. For illustration the product being flaked can be any product for which this particular morphology could be beneficial, such as to facilitate dissolution, dispersion, decomposition, release into the surroundings, uptake by relevant organisms, or any such process in which a relatively increased specific surface area can be beneficial to the product efficiency.

EXAMPLES

Example 1: Dry Flaking of Tastants In this example, tastants selected from sugar, salt and ground coffee, as commercially available, were flaked while being fed as dry powders. Sugar and salt represent water-soluble materials, whereas coffee despite containing water-soluble constituents is considered as a water-insoluble material. The dry samples were fed to an apparatus having a nip as schematically illustrated in Figure 5 and consisting of three rotating cylinders. Both rotating cylinders 510 and 530 were made of stainless steel 17-4 PH' (having a Vickers hardness of 240 Fly and an average surface roughness./2,, of less than 1600 nrn), and had a diameter of 30 cm.

Rotating cylinder 520, positioned between cylinders 510 and 530, was made of tungsten carbide and had a diameter of 1 cm. All three cylinders shared a similar axial length of 25 cm. They were counter-rotated at a similar speed of 20 rounds per minute (rpm), while being urged into contact by a calculated Hertz contact pressure of up to 750 MPa, using a compressing mechanism providing a force of 1.5 ton-force. The granulated sugar was fed to the nip, the surfaces of the rotating cylinders being at ambient temperature of about 23°C. After a single application of 1 g of sugar and 6 passages through the nip, flaked sugar was collected using a doctor blade coated with a ceramic material, the blade being suitably positioned and oriented to detach the flakes from their underlying surface. This experiment and the resulting flakes were named DF-1. SEM-FIB micrographs were taken by placing the particles being studied on an aluminium pin type SEM mount covered in double sided adhesive carbon tape, the images were captured at a magnification of X100 with an electron high tension (EHT) voltage of 1.2 kV and an aperture size of 30 gm (using a Crossbeam 340 microscope of Zeiss). The samples were measured at the beginning and end of the flaking process, and their average dimensions were assessed on at least 10 individual grains or flakes detectable in the field of view. All initial grains were approximated to spheres, even if slightly more cubic in shape, so that the original size of the tastants is presented as an average diameter. Figure 8A is a picture of sugar grains, before being fed to the apparatus, while Figure 8B is a picture of sugar flakes as obtained under the afore described conditions.

The conditions and results obtained by the afore detailed and similar dry flaking methods are summarized in Table 1 for all tastants accordingly prepared and fed in a same quantity. In this and following tables, SS stands for stainless steel 17-4 PW, WC stands for tungsten carbide, and 0 stands for the average diameter of the grains being fed or for the diameter of the rotating cylinders.

Table 1.

DF-1 DF-2 DF-3 Tastant Sugar Salt Coffee Initial mean dimensions 0 -500 gm 0 -30 p.m 0 -600 gm Nip as in Fig. 5 Fig. 5 Fig. 5 1. cylinder SS 0 30 cm SS 0 30 cm SS 0 30 cm 2nd cylinder WC 0 1 cm WC 0 1 cm WC 0 1 cm n rd _c y linder SS 0 30 cm SS 030 cm SS 0 30 cm Speed 20 rpm 20 rpm 20 rpm Temperature 23°C 23°C 23°C Pressure 750 MPa 900 MPa 750 MPa No. of passages through nip 6 7 5 Final mean dimensions t -6 gm t -3 gm t -18 min L -400 pm Asp -67 L -100 pm Asp -33 L -300 jinn Asp -16 Example 2: Paste Flaking of Tastants In this example, granulated coffee having an average diameter of about 500 pm was flaked while being fed as a paste of dry powders dispersed in a viscous medium to an apparatus having a nip as schematically illustrated in Figure 4. The first and second rotating cylinders 410 and 420 were identical and made of stainless steel 17-4 PH® (having a Vickers hardness of 240 FIV and an average surface roughness R, of less than 1600 nm), and had a diameter of 30 cm for an axial length of 25 cm. They were counter-rotated at a similar speed of 60 rpm, while being urged into contact by a calculated pressure of 370 MPa, using a compressing mechanism providing a force of 7.5 ton-force. The granulated coffee was mixed at a weight ratio of 1:10 into a viscous medium made of 20 wt.% xanthan gum in water, this medium having a dynamic viscosity of about 10,000 mPa.s as measured at room temperature in an appropriate rheometer (Thermo Scientific (Germany) Haake Mars 111) with a C20/1° spindle, a gap of 0.052 mm, a volume of 0.04 ml and a shear rate -oscillation frequency sweep of 0.1-100 Hz, Gamma 1%. The resulting paste was fed to the nip, the surfaces of the rotating cylinders being at ambient temperature. After a single application of 0.5 g of paste and 20 passages through the nip, flaked coffee at least partially enrobed with the viscous medium was collected from the surface of the cylinder using a suitably oriented doctor blade as previously detailed. This experiment and the resulting flakes were named PF-1. SEM-FIB micrographs were taken, as previously described, at the beginning and end of the flaking process, and average dimensions were assessed on at least 10 individual grains or flakes detectable in the field of view. Figure 9A is a picture of coffee grains, before being fed to the apparatus, while Figure 9B is a picture of coffee flakes as obtained under the afore described conditions, both being at a magnification of X100.

The conditions and results obtained by the afore detailed flaking method are summarized in Table 2.

Table 2 PF-1

Tastant Coffee Initial mean dimensions 0 -500 p.m Viscous medium 20 wt.% of xanthan gum in water Tastant:medium w/w-ratio 1:10 Nip as in Fig. g 4 1st cylinder SS 0 30 cm 2nd cylinder SS 0 30 cm PF-1 Speed 60 rpm Temperature 23°C Pressure 370 MPa No. of passages through nip 20 Final mean dimensions t -5 pin L -100 p.m Asp -20 Example 3: Liquid Flaking of Materials Including Tastants In this example, materials, whether water-soluble or water-insoluble, were flaked while being fed as a solution or dispersion in a non-viscous liquid to an apparatus having a nip as schematically illustrated in Figure 4 or in Figure 5. The materials tested, which may serve as tastants and/or other purposes in additional industries, included A: salt, citric acid, sodium bicarbonate, and sodium phosphate monobasic and dibasic, which are considered water-soluble materials; and B: calcium carbonate, a dye, magnesium stearate and silica, which are considered water-insoluble materials.

Regarding non-limiting prospective uses of the water-soluble materials tetsted, both salt and citric acid (E330) are known for their dual roles as flavor enhancers and food preservatives, but both may fulfill many additional functions in other industries. While sodium bicarbonate (E500) can provide for a slightly bitter and salty taste, it is better known for its use as leavening agent for baked goods, while having a variety of additional uses in other industries (e.g., as an antacid used in medicine to relieve heartburn and acid indigestion, as a stain remover in personal care or cleaning products, etc.). Sodium phosphate monobasic (E339(i)) and dibasic (E339(ii)), also known as monosodium phosphate (MSP) and disodium phosphate (DSP), are considered relatively tasteless, but can be used as food emulsifiers, thickeners, leavening agents, anti-caking agents or pH controlling agents. In other industries they can be used in detergents and cleaning product, while in medicine they are used as a laxative (e.g., prior to a colonoscopy).

Regarding, non-limiting prospective uses of the water-insoluble materials tested, silicon dioxide, also known as silica, can be used for a variety of purposes such as in the construction industry to produce concrete, in hydraulic fracturing (when in its crystalline form, in the production of glass, as a sedative, in the production of elemental silicon, as an anti-caking agent in powdered foods like spices, as a fining agent in juice, beer, and wine, in pharmaceuticals for making tablets and in toothpaste to remove tooth plaque, to name a few. Near Infra-Red (NIR) dyes, such as N1R983A of QCR Solutions Corp, can served in the preparation of images to be read by specialized infrared detectors, such as serving in security solutions from QR codes to semi-disappearing pictures, or in chemical biology or medicine as research tool or diagnostic imaging. Tumor-specific imaging by N1R dyes may open the way to photothermal, and photodynamic therapies. Magnesium stearate can serve in the food industry, as well as in the pharmaceutical one, typically as an emulsifier, a binder, a thickener, as well as an anticaking, lubricant, release, and antifoaming agent. The many uses of calcium carbonate have been previously illustrated and shall not be repeated.

As to the procedure, regular table salt (sodium chloride, NaCI) having an average diameter of about 500 i_tm was first briefly grounded in a coffee grinding machine to produce a finer salt with grains having an average diameter of about 50 pm. The extra fine salt was mixed at room temperature at a weight ratio of 1:3 into water until complete dissolution. For reference, this solution is considered nearly saturated, the weight percent concentration of the sodium chloride per total weight of the solution being 25 wt.%, while a solution would be saturated at about 35 g of sodium chloride per 100 g pure water (i.e. at about 26.5 wt.% of salt per total weight of the solution) at the same temperature. The resulting liquid stock was fed to the nip of an apparatus as schematically illustrated in Figure 4. Both rotating cylinders 410 and 420 were made of stainless steel 17-4 PH' (having a Vickers hardness of 240 HV and an average surface roughness Ra of less than 1600 nm), had a diameter of 30 cm and an axial length of 25 cm.

They were counter-rotated at a similar speed of 60 rpm, while being urged into contact by a calculated Hertz contact pressure of 370 MPa using a compressing mechanism providing a force of 7.5 ton-force, the surfaces of the rotating cylinders being at ambient temperature. After a single application of 0.5 ml of liquid and 38 passages through the nip, salt flakes were collected using a suitably oriented doctor blade as previously detailed. This experiment and the resulting flakes were named LF-1. SEM-FIB micrographs were taken, as previously described, at the beginning and end of the flaking process, and average dimensions were assessed on at least 10 individual grains or flakes detectable in the field of view. Figure 10A is a picture at a magnification of X100 of salt grains, before being dissolved and fed to the apparatus, while Figure 10B is a picture at a magnification of X1,000 of salt flakes as obtained under the afore described conditions.

The conditions and results obtained by the afore detailed and similar liquid flaking methods are summarized in Table 3A and following paragraphs, when the materials were water-soluble, and in Table 3B, when the materials were water-soluble. In each part of this table and example, water stands for pure double distilled water and Citric Ac. stands for citric acid. For the sake of LF-2 and LF-3, the surfaces of rotating cylinders 410 and 420 were pre-heated to the desired temperature by blowing hot air towards the rotating surfaces. Furthermore, the liquid stocks of salt solution and salt dispersion were applied at the same temperature (as obtained by stirring the liquid stocks on a hot plate). For the sake of LF-4 and LF-5, the apparatus included a series of nips as schematically illustrated in Figure 5. For LF-4, rotating cylinders 510, 520 and 530 were as described in Example 1. For LF-5, a series of six identical cylinders linearly aligned was used, allowing for a single passage through any of the nips, continuous application of liquid stocks on the first cylinder and continuous collection of tastant flakes on the sixth cylinder. For LF-6, the configuration was similar to the one described for LF-1, except for the nearly saturated stock of tastant being made of citric acid (1-10C(CO211)(CH2CO21-1)2).

Table 3A

LF-1 LF-2 LF-3 LF-4 LF-5 LF-6 Tastant Salt Salt Salt Salt Salt Citric Ac.

Initial mean 0 -50 pm 0 -50 pm 0 -50 pm 0 -50 pm 0 -50 pm 0 -50 pm dimensions Non-viscous liquid Water Water Water Water Water Water Tastant:liquid w/w ratio 1:3 1:3 2:3 1:3 1:3 1:1 Nip as in Fig. 4 Fig. 4 Fig. 4 Fig. 5 Fig. 5 Fig. 4 Cylinders 2xSS 030cm 2xSS 030cm 2x SS 030cm 2xSS 6xSS 030cm 2xSS 030cm 030cm + WC Olcm Speed 60 rpm 60 rpm 60 rpm 20 rpm 20 rpm 60 rpm Temperature 23°C 60°C 60°C 23°C 23°C 23°C Pressure 370 MPa 370 MPa 370 MPa 900 MPa 250 MPa 370 MPa No. of passages through nip 38 7 5 26 1 40 Final mean dimensions t -3 pm t -5 pm t -4 pm t -1 pm t -1 pm t -4 pm L-150 pm Asp -50 L-400 pm Asp -80 L-500 pm Asp -125 L-100 pm Asp -100 L -50 pm Asp -50 L -20 pm Asp -5 Figure 11A is a picture at a magnification of X100 of salt grains, before being dispersed and fed to the apparatus, while Figure 11B is a picture at a magnification of X1,000 of salt flakes as obtained under the conditions above described for LF-3.

In LF-7, not reported in the table, the configuration was similar to the one described for LF-1, except that instead of feeding a solution, the liquid stock was fed as a dispersion. The stock was prepared by dispersing salt into a liquid in which it is not soluble. Fine salt grounded to have an average diameter of about 50 pm was dispersed at 3 g in 100 ml of isopropyl alcohol.

It was found that after 10 passages through the nip, flakes of sodium chloride having an average thickness t of about 3 p.m, an average longest planar dimension L of about 400 p.m, with an aspect ratio ASP of approximately 133. The thickness is comparable to LF-1, the planar dimension of the flakes (and the aspect ratio) being relatively larger. Notably, as isopropyl alcohol is more volatile than water, in particular at room temperature in which the experiment was carried out, the flakes were obtained more rapidly from the dispersion in the alcohol than from the solution in water. Figures 12A and 12B are pictures at a magnification of X100 of salt, respectively as grains before being dispersed and fed to the apparatus in a liquid improper for their solubilization, and as flakes obtained under the conditions above described for LF-7.

For LF-8 to LF-10, not reported in the table, the configuration was similar to the one described for LF-1, except that the cylinders were rotated at a speed of 120 rpm, instead of 60 rpm.

In LF-8, the nearly saturated stock of water-soluble material was made by dissolving sodium bicarbonate (NAN:03) at a 1:10 weight ratio in water. It was found that after 40 passages through the nip, the sodium bicarbonate which was globular with an average diameter of about 70 pm before being dissolved yielded by this method flakes having an average thickness t of about 1.5 pm, an average longest planar dimension L of about 40 p.m, with an aspect ratio ASP of approximately 27.

In LF-9, the nearly saturated stock of water-soluble material was made by dissolving sodium phosphate dibasic (Na 21-IP04) at a 1:10 weight ratio in water. It was found that after 10 passages through the nip, the sodium phosphate dibasic which was globular with an average diameter of about 200 pm before being dissolved yielded by this method flakes having an average thickness t of about 4 p.m, an average longest planar dimension L of about 60 pm, with an aspect ratio ASP of approximately 15.

In LF-10, the stock of water-soluble material was made by dissolving sodium phosphate monobasic (NaWPO4) at a:74 weight ratio in water. It was found that after 10 passages through the nip, the sodium phosphate monobasic which was globular with an average diameter of about 400 pm before being dissolved yielded by this method flakes having an average thickness t of about 6 pm, an average longest planar dimension L of about 150 pm, with an aspect ratio ASP of approximately 25. Figures 13A and 13B are pictures at a magnification of X100 respectively of grains of sodium phosphate, before being dispersed and fed to the apparatus, and of flakes as obtained under the conditions above described for LF-10.

In LF-11, not reported in the table, the cylinders were made of zirconia (having a Vickers hardness of 1300 HV and an average surface roughness Ra of about 250 nm) instead of stainless steel and each cylinder of the pair had a diameter of 6 cm instead of 30 cm. A liquid stock made of a solution of extra fine salt prepared as described in LF-1 was applied at room temperature to a cylinder while rotating at 300 rpm. The cylinders of zirconia were urged into contact by a calculated Hertz contact pressure of 350 MPa using a suitably set compressing mechanism. The flakes obtained after 150 passages through the nip had an average thickness t of about 5 pm, an average longest planar dimension L of about 400 pm, with an aspect ratio ASP of approximately 80.

The materials and conditions for the preparation of LF-12 to LF-15, relating to the flaking of water-insoluble materials whether dispersed or dissolved, and the flakes obtained thereby are summarized in Table 3B, in which Mg Ste. Stands for magnesium staearate. For all samples, the configuration of the nip was according to Figure 4, wherein two cylinders of stainless steel each having a diameter of 30 cm were rotated at 60 rpm and the liquid stocks and surfaces were at room temperature. As furthermore, the pressure applied was of 370 MPa for each sample of this series, this information is omitted from the following table.

Table 3B

LF-12 LF-13 LF-14 LF-15 Material CaCO3 Mg Ste. SiO2 Dye Initial mean dimensions 0 -20 pm 0 -10 pm 0 -10 pm 0 -50 pm Non-viscous liquid Water Water Water Acetone Materi al: liqui d w/w ratio 1:20 1:30 1:52 1:20 No. of passages through nip 30 40 38 15 Final mean dimensions t -3 pm L-60 pm Asp -20 t -0.8 pm t -1.5 pm t -0.7 pm L-16 pm L-30 pm L-20 pm Asp -20 Asp -20 Asp -28 LF-12 to LF-14 represent dispersions, the water-insoluble materials not dissolving in water at their added concentration, whereas in LF-15 the non-aqueous liquid (namely acetone) was adapted to dissolve the NIR dye.

Figures 14A and 14B are pictures of calcium carbonate at a magnification of X1,000 and X100, respectively of grains, before being dispersed and fed to the apparatus, and of flakes as obtained under the conditions above described for LF-12.

Figures 15A and 15B are pictures of NIR dye N1R983A at a magnification of Xi 000, respectively of grains, before being dissolved and fed to the apparatus, and of flakes as obtained under the conditions above described for LF-15.

Example 4: Improved Dissolution Rate of Flakes In this example, flakes prepared according to Example 3 were tested for their rates of dissolution in water at room temperature, as compared to the rate of dissolution of different types of unflaked references. Unless otherwise stated, all experiments reported in this and following examples were performed on flakes actively detached from the surface of the rotating cylinders upon which they were formed using a suitably oriented doctor blade.

The dissolution rates of flakes made of salt were determined by measuring the electrical conductivity of various salt compositions prepared from sample tastants or references dissolved in water, the dissolution of the salt changing the ionic conductivity of the solution. 40 mg of salt samples previously dried for at least two hours at 120°C and kept thereafter at room temperature in a dessicator, were added to 80 ml of double distilled water at room temperature under ongoing stirring at 400 rpm. Conductivity was measured using a Keithley 2750 Multimeter, by applying an alternating voltage via electrodes immersed in the solution samples and measuring the resulting current. Conductivity, hence measured current, was increasing as long as the salt was dissolving, then reached a plateau. The time that lapsed between the addition of the salt and plateau values of current was recorded. Each conductivity measurement was repeated at least three times and the duration of dissolution till current stabilized to plateau values, as measured with a chronometer in seconds, before and after flaking is reported as an average of all repeats in Table 4.

Table 4

Sample Table Salt Extra Fine Salt Flake LF-1 Salt Dimensions 0 -500 j,im Asp -1 0 -50 j,im Asp -1 t -3 jam L -150 iim Asp -50 Dissolution of tastant 8.7s 3.4s 0.9s The rate of dissolution was also qualitatively assessed by placing a known amount of a sample on a glass slide and adding at a distance therefrom a known volume of a solvent, in an amount sufficient to dissolve the solid by capillarity once a liquid bridge is formed by the operator while observing the outcome using a confocal microscope under a magnification of x228. For each material, two samples were tested, first the unflaked raw material, then the flaked version of the same. Observations were made in repeats for all samples. By this method it was found that the rates of dissolution of sodium phosphate monobasic monohydrate and sodium phosphate dibasic in water were visibly faster when these materials were flaked as described in LF-10 and LF-9, respectively.

Example 5: Density of Tastants In this example, tastant flakes made of salt and prepared according to Example 3 were tested for their bulk and tap densities, as compared to the bulk and tap densities of unflaked standard salt which served for their preparation, as references.

The bulk density p8 of each sample was measured by weighing the mass of a previously dried sample filling in a known bulk volume Vii as measured in a finely graduated cylinder. Then the vessel was repeatedly tapped until the volume no longer contracted, the final constant value serving to estimate the tapped volume VT from which the tapped density in was calculated. Typically, the tapping lasted up to one minute at a pace of two taps per second.

Flaked tastants were collected from two sources, first when spontaneously detaching from the surface of the rotating cylinder, secondly when actively detached by placing a blade on the surface of the rotating cylinder, the blade being oriented to peel away the flakes. The results are presented in Table 5 in which spontaneously detached flakes are annotated by a S superscript and actively detached flakes are annotated by an A superscript.

Table 5

Tastant pH pr Extra fine salt 0.87 g/cm3 1.26 g/cm3 Flaked tastant LF-ls 0.14 g/cm3 0.39 g/cm3 Flaked tastant LF-1 A 0.08 g/cm3 0.14 g/cm3 Flaked tastant LF-11s 0.22 g/cm3 0.49 g/cm3 Example 6: Crysta lographic Analysis of Crystalline Tastants Analysis of the crystallographic structure of salt flakes by X-ray powder diffraction (XRPD) was performed on pellets of compressed flakes. The data were collected on a Panalytical Empyrean III multi-purpose diffractometer (Ka radiation, k=1.541 A) equipped with a pixCEL 3D detector in 1D line-detector mode, and with an X-ray tube operated at v=45 kV, I = 40 mA. Each sample was mounted directly in a stainless-steel, ring, back-filled sample holder. The sample was rotated at 8 rotations/min during the measurement, which was run from 5-140° 20. Phase identification and Size-Strain analysis by Reitveld refinement was performed using the High Score Plus powder diffraction data analysis suite (version 5.1), coupled with the ICDD (International Centre for Diffraction Data) Powder Diffraction File (PDF-4+) database (2022).

Pellet 1 was made of grains of standard table salt having an average diameter of about 500 p.m (which served when grounded to form the extra fine salt), pellet 2 was made of grains of extra fine salt having an average diameter of about 50 p.m (which served when dissolved to form the flakes of LF-1) and pellet 3 was made of the resulting salt flakes LF-1 prepared as described in Example 3.

The diffraction peaks obtained from the analyzed samples appeared to be relatively similar with respect to their respective positions and included known characteristic peaks of sodium chloride such as detected at about 31.7°, 45.4°, 66.2°, and 75.3°, to name a few. The diffraction peaks of the flaked sample seemed mildly broader than their counterparts as obtained from the reference granular sample. Phase identification indicated that all samples contained more than 99.5 wt.% of NaCl. The microstrain values only (in percentage) and the crystallite size of each sample are reported in Table 6.

Table 6

Pellet 1 Pellet 2 Pellet 3 Table salt 0 -500 tm Extra fine salt 0 -50 tm Flaked salt LF-1 Crystallite Size > 2 ttrn > 2 p.m 543 A Strain [%] 0.021 0.052 0.176 Example 7: Specific Surface Area of Flakes Flakes of materials prepared according to Examples 1-3 can be tested for their specific surface area, which can be compared to the specific surface area of the respective material before flaking serving as reference, as follows. The surface area of the samples is measured by gas adsorption techniques using an ASAP 2020 Accelerated Surface Area and Porosimetry System of Micromeritics Instrument Corporation according to standard methods. Briefly, samples are weighted and placed in a measurement glass tube with a known free space in which a filler rod is inserted, the tube being sealed with a frit seal adapted to allow entry and exit of gas during the analysis. The samples are allowed to dry overnight under vacuum. The dry samples are then subjected to an evacuation phase under heating, the target temperature of 30°C being reached at a ramp up rate of 1 °C/min. The evacuation is performed at a rate of 5 mmHg/s, till a vacuum of 10 ttmHg is obtained. The measurement glass tubes are then transferred to liquid nitrogen for the phase of nitrogen gas insertion which lasts 10 minutes to enable physical sorption of the molecule to the surface of the dry samples. The excess nitrogen gas is then evacuated under vacuum of 100 mmHg and measurements are collected for 120 minutes of analysis with an equilibrium interval of 5 seconds. Each measurement is repeated at least three times, and the specific area of each sample is calculated by the BET method.

Example 8: Flowability of Flakes The effect of the morphology of materials on their flowability can be determined by any suitable method. For illustration, a weighed mass of sample can be timed as it flows through the calibrated orifice of a flowmeter funnel, as described in ASTM B213 for a Hall flowmeter or in ASTM B964 for a Carney flowmeter, if the flakes or reference grains of water-soluble material fail to freely flow in a regular and constant way in the former instrument.

The experiment is preferably conducted in a laboratory with controlled temperature and humidity to ensure a relatively low relative humidity and stable temperature conditions. A dry and clean flowmeter funnel is held by a stand placed on a stable workbench, as the flow is to be measured unaided. As the discharge orifice of the funnel is blocked, a predetermined weight of the sample previously dried for 2 hours at 120°C is carefully placed in the funnel, without tapping, vibrations or movement that would artificially stack the sample. As the discharge orifice is open, a timing device is simultaneously started to monitor the time elapsing till the last of the sample exits the orifice. More than one flow test may be run, each time with a fresh quantity of dry sample, and the flow times corresponding to the same sample can be averaged. Flow times of different samples, or averages of repeats run on different samples, can be compared. The flow rates may be calculated and normalized according to a funnel dependent factor.

Example 9: Organoleptic Test of Tastants The effect of the morphology of the tastants on the taste that can be accordingly perceived can be tested with human volunteers. The tastant, before and after flaking as herein disclosed, can be tested "as is", or once applied on or mixed with a food product otherwise deprived of the tastant. For illustration, the tastant can be applied on a popped popcorn or mixed in a relatively tasteless edible gel. A same proportion of reference tastant or flaked tastant can be applied on or mixed with the food, to establish how much stronger is the taste provided by the tastant flakes. Conversely, once a contents of reference tastant is set to provide a satisfactory taste, food samples can be prepared with decreasing amounts of the tastant flakes, until a similar satisfactory taste is obtained. By this methodology, one can establish by how much the quantity of tastant can be reduced when using the flaked tastants instead of the standard reference tastant.

The trained panelists after rinsing their mouth with spring water in-between each evaluation, ingest a similar amount of food samples and assign to each a taste strength value ranging from zero (no taste change, as compared to a food control deprived of any added tastant) to ten for the highest strength intensity. Each panelist is repeating the organoleptic test at 5 minutes interval, the food samples with reference or flaked tastant being randomly assigned at each round of evaluation.

The taste scores obtained for each food sample are summed for all panelists and repeat tests, and divided by the total number of tests, to obtain a calculated mean taste score for each food sample. The results obtained for each food sample can be compared and analyzed.

Summary of Working Examples

As can be seen from the above tables and results reported therein, the present methods and apparatus implementing them are suitable to rapidly manufacture micro flakes, some experiments providing sub-micro flakes in sufficient enough proportion to enable their separation. All flakes, regardless of the size range of their average thickness, displayed a dimensionless aspect ratio of at least about 5 (see LF-6), most being above at least 20.

While the feasibility of the present flaking method and apparatus was mainly demonstrated with tastants, this is not limited to such type of compounds and a variety of water-soluble and water-insoluble materials having additional purposes in industries other than the food industry have also been successfully flaked. Considering flakes of water-soluble materials manufactured by the application of a relatively non-viscous liquid to a movable surface forming with a countersurface a nip of confinement, flakes could be prepared when fed either as solutions (see LF-1 to LF-6, and LF-8 to LF-11) or dispersions (see LF-7). The same was true for water-insoluble materials which have been flaked either from dispersions (see LF-12 to LF 14) or from solutions (see LF-15).

Advantageously, the flakes prepared by the present methods displayed an improved rate of dissolution as compared to the respective reference tastant before flaking. The improvement was an about 10-fold acceleration of the dissolution when quantitatively measured for salt (see LF-1). Interestingly, the bulk and tapped densities of the actively detached tastant flakes of salt that displayed the accelerated dissolution were also about 10% of the bulk or tapped density of the reference tastant, respectively. Remarkably, when the tastant was a material having a crystalline structure, the flaked version of the tastant displayed a structure having at least about 3-times more microstrains than the crystal of the reference tastant originally dissolved to form the flakes. The size of the crystallites was also found to be at least about 36-times smaller for the flakes than for the reference granular tastant, further supporting that tastant flakes prepared as herein disclosed have been subjected to constrains (e.g., compressive forces as perceived during confinement in the nip(s)) normally absent from naturally growing crystals. The methods have been found applicable to different materials which provide a wide range of activities to the flakes, not being limited to taste or the food industry.

It is appreciated that certain features of the disclosure, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the disclosure, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination or as suitable in any other described embodiment of the disclosure. Certain features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.

Although the present disclosure has been described with respect to various specific embodiments presented thereof for the sake of illustration only, such specifically disclosed embodiments should not be considered limiting. Many other alternatives, modifications and variations of such embodiments will occur to those skilled in the art based upon Applicant's disclosure herein. Accordingly, it is intended to embrace all such alternatives, modifications and variations and to be bound only by the spirit and scope of the disclosure and any change which come within their meaning and range of equivalency.

In the description and claims of the present disclosure, each of the verbs "comprise", "include" and "have", and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of features, members, steps, components, elements or parts of the subject or subjects of the verb. Nevertheless, it is contemplated that the compositions of the present teachings also consist essentially of or consist of, the recited components, that the methods of the present teachings also consist essentially of, or consist of, the recited process steps, and that the apparatus of the present teachings also consist essentially of or consist of the recited devices.

Positional or motional terms such as "upper", "lower", "right", "left", "bottom", "below", "lowered", "low", "top", "above", "elevated", "high", "vertical", "horizontal", "front", "back", "backward", "forward", "upstream" and "downstream", as well as grammatical variations thereof, may be used herein for exemplary purposes only, to illustrate the relative positioning, placement or displacement of certain components, to indicate a first and a second component in present illustrations or to do both. Such terms do not necessarily indicate that, for example, a "bottom" component is below a "top" component, as such directions, components or both may be flipped, rotated, moved in space, placed in a diagonal orientation or position, placed horizontally or vertically, or similarly modified.

As used herein, the singular form "a", "an" and "the" include plural references and mean "at least one" or "one or more" unless the context clearly dictates otherwise. As used herein, 30 the term at least one of A and B is intended to mean either A or B, and may mean, in some embodiments, A and B. Unless otherwise stated, the use of the expression "and/or" between the last two members of a list of options for selection indicates that a selection of one or more of the listed options is appropriate and may be made.

The word "exemplary" is used herein to mean "serving as an example, instance or illustration". Any embodiment described as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments and/or to exclude the incorporation of features from other embodiments.

As used herein, unless otherwise stated, adjectives such as "substantially", "approximately" and "about" that modify a condition or relationship characteristic of a feature or features of an embodiment of the presently disclosed subject matter, are to be understood to mean that the condition or characteristic is defined to within tolerances that are acceptable for operation of the embodiment for an application for which it is intended, or within variations expected from the measurement being performed and/or from the measuring instrument being used. For example, when the term "about" or "approximately" precedes a numerical value, it may indicate +/-15%, or +/-10%, or even only +/-5%, or any other suitable +/-variation within such ranges, and in some instances may indicate the precise value. Furthermore, unless otherwise stated, the terms (e.g., numbers) used in an embodiment of the presently disclosed subject matter, even without such adjectives, should be construed as having tolerances which may depart from the precise meaning of the relevant term but would enable the embodiment or a relevant portion thereof to operate and function as described, and/or as understood by a person skilled in the art.

Claims

CLAIMS1. A method for manufacturing flakes, the method comprising: a) providing a liquid stock comprising at least one material dissolved or dispersed in a liquid; b) applying the liquid stock to a first movable surface, so as to form thereon a thin film of liquid stock; c) removing at least a part of the liquid from the thin film of liquid stock, so as to cause precipitation of the material(s) into a thin coat of precipitated materia1(s); and e) urging into contact the first movable surface and a countersurface one against the other to form a nip therebetween and confining the thin coat of precipitated material(s) into the nip, so as to obtain flakes made from said material(s), the flakes having an average thickness of at most 20 i;tm, at most 10 um, at most 5 um, or at most 1 i;tm and an aspect ratio between the longest planar dimension of the flakes and their thickness being on average of at least 5:1, at least 10:1, or at least 15:1.
2. A method as claimed in claim 1, wherein the liquid stock is applied by an applicator, the first movable surface and the applicator being in relative motion during the application step, and at least one of the formation of the thin film of liquid stock, the removal of at least a part of the liquid, and the obtention of the flakes is caused by a passage through the nip.
3. A method as claimed in claim 1 or claim 2, further comprising forming the thin film of liquid stock prior to passage through the nip.
4. A method as claimed in any one claim 1 to claim 3, wherein the liquid is being removed at least in part by passing the thin film of liquid stock more than once through the nip or at least one different nip.
5. A method as claimed in any one of claim 1 to claim 4, wherein the flakes are obtained by passing and confining the thin coat of precipitated material(s) more than once through the nip or at least one different nip.
6. A method as claimed in any one of claim 1 to claim 5, wherein the first movable surface is the outer surface of a first rotating cylinder.
7. A method as claimed in any one of claim 1 to claim 6, wherein the countersurface is the outer surface of a second rotating cylinder.
8. A method as claimed in any one of claim 1 to claim 7, wherein removing at least a part of the liquid includes evaporating the liquid.
9. A method as claimed in any one of claim 1 to claim 8, wherein the liquid stock is applied on the first movable surface at a temperature higher than ambient temperature and lower by at least 5°C than a boiling temperature of the liquid.
10. A method as claimed in any one of claim 1 to claim 9, wherein at least one of the first surface, the counter surface, and any other surfaces forming an at least one different nip are heated to a temperature higher than ambient temperature.
11. A method as claimed in any one of claim 1 to claim 10, wherein a force applied to urge the first movable surface into contact with the counter surface, or to urge any other surfaces into contact to form an at least one different nip, is such that a pressure exerted thereby at each nip is independently between 10 MI3a. and 1,500 MPa, between 50 MPa and 1,250 MPa, or between 100 MI'a and 1,000 MPa.
12. A method as claimed in any one of claim 1 to claim 11, further comprising collecting the flakes made from the material(s).
13. A method as claimed in any one of claim 1 to claim 12, wherein the liquid stock is continuously applied, and the obtained flakes are continuously collected.
14. A method as claimed in any one of claim 1 to claim 13, wherein the material(s) are crystals.
15. A method as claimed in any one of claim 1 to claim 14, wherein at least one material of the one or more materials is a tastant.
16. An apparatus for producing flakes made from a material, the flakes having an average thickness of at most 20 pm and an aspect ratio between the longest planar dimension of the flakes and their thickness being on average of at least 5:1, the apparatus comprising: a) a feeder adapted to dispense intermittently or continuously a dose or flow rate of a liquid stock including at least one material dissolved or dispersed therein; b) a support structure for supporting two or more rotatable cylinders; c) a compression mechanism for urging the surfaces of each two adjacent cylinders of the two or more rotatable cylinders into contact at a respective nip therebetween; d) a drive mechanism for causing the rotatable cylinders to rotate; and e) a collector for collecting the flakes from a thin coat of precipitated material(s), following a removal of at least a part of the liquid from the liquid stock; wherein the feeder is configured to apply the liquid stock on a first rotatable cylinder of the two or more cylinders and the collector is adapted to collect the flakes after one or more passages of a thin film of the liquid stock through the one or more nips of the two or more rotatable cylinders.
17. An apparatus as claimed in claim 16, further comprising a levelling device adapted to level the liquid stock into a thin liquid film prior to passage through a first nip of the one or more nips.
18. An apparatus as claimed in claim 16 or claim 17, further comprising at least one of A-a heating device to heat at least one of the liquid stock to be dispensed by the feeder and any of the surfaces of the two or more rotatable cylinders; and B-a detaching device adapted to detach the flakes from the thin coat of precipitated material(s) for their collection by the collector.
19. An apparatus as claimed in any one of claim 16 to claim 18, wherein the outer surface of each of the two or more rotatable cylinders is independently made of or coated with, a material fulfilling at least one of the following features: i) the material is wettable by the liquid stock; and b) the material has a Vickers hardness between 50 HV and 10,000 HV, between 100 HV and 5,000 HV, between 150 HV and 3,500 HV, or between 200 HV and 2,000 HV.
20. An apparatus as claimed in any one of claim 16 to claim 19, wherein at least one material of the one or more dissolved or dispersed materials is a tastant.
21. Flakes made from at least one material, the flakes having thin planar dimensions wherein each flake has a longest dimension and a plurality of flakes has an average longest dimension (L) in the plane, wherein each flake has a largest thickness and a plurality of flakes has an average largest thickness (1) from one side of the plane to the other side, and wherein a flake has a dimensionless aspect ratio between a longest dimension and a largest thickness so that the plurality of flakes has an average aspect ratio (Asp=L/t) of at least 5:1; the flakes being characterized by at least one, at least two or at least three of the following structural features: a) t is at most 20 pm, 18 gm, 16 pm, 14 pm, 12 pm, or 10 pm; b) t is at most 9 pm, 8 gm, 7 pm, 6 pm, 5 gm, 4 pm, 3 gm, or 2 pm; c) t is at most 1 pin, 0.9 gm, 0.8 pm, 0.7 pm, 0.6 pm, 0.5 pm, 0.4 pm, or 0.3 gm; d) t is at least 50 nm, at least 100 nm, at least 150 nm, or at least 200 nm; c) L is at most 500 p.m, at most 400 p.m, at most 300 p.m, at most 200 um, at most 100 gm, or at most 50 um; d) L is at least 5 um, at least 7.5 um, at least 10 um, at least 12.5 gm, or at least 15 um; e) Asp is at least 10:1, at least 20:1, at least 30:1, or at least 40:1; 0 Asp is at most 150:1, at most 125:1, at most 100:1, at most 75:1, or at most 50:1.g) the flakes have a specific surface area of at least 0.01 m2/g, at least 0.05 m2/g, at least 0.1 m2/g, at least 0.2 m2/g, at least 0.3 m2/g, at least 0.4 m2/g, or at least 0.5 m2/g; h) the flakes have a specific surface area of at most 10 m2/g, at most 8 m2/g, at most 6 m2/g, at most 4 m2/g, or at most 2 m2/g; and i) the, or each, material of the flakes is a crystalline material.
22. The flakes as claimed in claim 21, prepared by a method according to any one of claims 1 to 15, and/or using an apparatus according to any one of claims 16 to 20.
23. The flakes as claimed in claim 21 or claim 22, wherein at least one material of the one or more materials making the flakes is a tastant.
24. A food comprising flakes as claimed in claim 23.
25. A method for reducing the amount of a tastant adapted to provide a desired taste to a food, the method comprising substituting flakes as claimed in claim 23 for at least a part of the tastant in the food.