FR3144743A1 - RECONSTITUTED PLANT LEAF INCLUDING STABILIZED NICOTINE - Google Patents

Abstract

The present invention relates to a reconstituted plant leaf comprising acid-stabilized nicotine.

Description

RECONSTITUTED PLANT LEAF INCLUDING STABILIZED NICOTINE

The present disclosure belongs to the field of devices for heating tobacco without burning it and relates to a reconstituted plant leaf comprising stabilized nicotine, the plant not being a tobacco plant.

A large number of devices for heating tobacco without burning it have been developed in order to avoid the formation of harmful constituents during the combustion of tobacco. By way of example, we can cite the applications published under the numbers WO 2016/026810 and WO 2016/207407 which describe such devices. Tobacco sticks are placed in these devices, the tobacco is then heated by the device to a temperature below the combustion temperature without being burned, which leads to the formation of an aerosol when the user draws air through the device. The aerosol generated replaces cigarette smoke and has advantageous organoleptic properties when inhaled by the user. This allows the user to inhale nicotine and tobacco flavors while significantly reducing the user's exposure to harmful components.

For the user to adopt these heating devices, it is important with said devices to have an experience as close as possible to that obtained with a conventional cigarette, that is to say, for each puff, satisfactory organoleptic properties and a similar level of nicotine.

Natural tobacco leaves may not be suitable for these heaters as they do not provide the user with a satisfactory experience.

Reconstituted tobacco is more suitable for these heating devices, because it makes it possible to easily apply a high level of aerosol-generating agent and generate a significant quantity of aerosol having interesting organoleptic properties and providing sufficient nicotine.

It may be advantageous to offer the user of these heating devices aromas different from those of tobacco. This is the reason why reconstituted plant leaves, such as those described in document WO 2019/043119, have been developed. The aerosols generated from these reconstituted plant leaves have satisfactory organoleptic properties. However, these reconstituted plant leaves do not contain nicotine. Consequently, the aerosols generated from these reconstituted plant leaves do not provide a fully satisfactory experience for heating device users and for the smoker since they do not provide nicotine.

To resolve this first technical problem, the inventors tried to add nicotine in neutral form to the leaves of reconstituted plants. However, they found that the nicotine added to the reconstituted plant leaves can be released during manufacturing and especially during storage of the reconstituted plant leaves and the consumables for heating devices comprising these reconstituted plant leaves. The aerosols generated from these reconstituted plant leaves include nicotine in neutral form but are not satisfactory because their quantity of nicotine is too low and the physiological absorption by the consumer of the neutral form of nicotine is too slow. Additionally, aerosols can also be too harsh.

To solve this second technical problem, the inventors tried to stabilize nicotine by adding an acid to form a nicotine salt. However, they found that aerosols generated from reconstituted plant leaves comprising a nicotine salt may still be unsatisfactory because, in certain circumstances:
- they include a quantity of nicotine even lower than that targeted,
- they are still too aggressive, and/or
- they have an unpleasant sour taste.

Technical problem

There is therefore a need for a reconstituted plant leaf comprising nicotine which generates an aerosol satisfactory for the user.

It is therefore to the merit of the inventors to have found that it is possible to meet this need by means of a reconstituted plant leaf comprising a nicotine salt and having a specific pH range.

Summary

A reconstituted plant leaf is proposed comprising:
- a fibrous support comprising plant fibers,
- an aerosol generating agent, and
- a plant extract,
in which the plant is not the tobacco plant,
characterized in that
it further comprises nicotine and an organic acid, or a nicotine salt, and
it has a pH of 4.9 to 7.0, especially 5.0 to 6.0.

Advantageously, in these pH ranges, the reconstituted plant leaf of the present invention generates an aerosol providing nicotine satisfactorily and not exhibiting unpleasant aggressiveness and acidic taste, that is to say a satisfactory aerosol for the user.

Without wishing to be linked to any theory, the inventors are of the opinion that these results can be explained by:
- the monoprotonated form of nicotine which is the main form of nicotine in the reconstituted plant leaf of the present invention. The monoprotonated form of nicotine results from the formation of the nicotine salt by a reaction between nicotine and organic acid. The monoprotonated form of nicotine is efficiently released into the aerosol when using the reconstituted plant leaf of the present invention in a heating device and is known to have a physiological absorption profile comparable to a conventional cigarette,
- increasing the proportion of the neutral form of nicotine in a reconstituted plant leaf having a pH greater than 7. The neutral form is volatile and is therefore easily released during the manufacture and especially during the storage of said leaf of nicotine reconstituted plant and consumables for heating device comprising said reconstituted plant leaf. In addition, the neutral form is more irritating and has slower physiological absorption than the monoprotonated form, and
- increasing the proportion of the diprotonated form of nicotine in a reconstituted plant leaf having a pH less than 4.9. The diprotonated form is too stable to be effectively released from said reconstituted plant leaf when the aerosol is generated, such that said aerosol may include an unsatisfactory amount of nicotine. In addition, the quantity of organic acid in free form increases in said reconstituted plant leaf so that the aerosol generated from said reconstituted plant leaf can have an unpleasant acidic taste and can even have deleterious physiological effects in certain cases. case.

In addition, the aerosol generated from the reconstituted plant leaf of the present invention has interesting organoleptic properties and its quantity is significant thanks to the plant extract and the aerosol generating agent. These organoleptic properties are advantageously different from the organoleptic properties of an aerosol generated from reconstituted tobacco leaves.

According to another aspect, a process for producing a reconstituted plant leaf as defined above is proposed, comprising the following steps:
a) passing plant fibers through a paper machine so as to produce a base sheet,
b) formation of a solution comprising:
- plant extract,
- the aerosol generating agent, and
- nicotine and organic acid, or nicotine salt,
c) bringing the solution into contact with the base sheet to obtain a moist reconstituted plant leaf, and
d) drying the wet reconstituted plant sheet to produce the reconstituted plant sheet.

A reconstituted plant leaf is proposed comprising:
- a fibrous support comprising plant fibers,
- an aerosol generating agent, and
- a plant extract,
in which the plant is not the tobacco plant,
characterized in that
it further comprises nicotine and an organic acid, or a nicotine salt, and
it has a pH of 4.9 to 7.0, especially 5.0 to 6.0.

The pH of the reconstituted plant leaf of the present invention is measured as follows:
- grind the reconstituted plant leaf to obtain particles less than 1 mm,
- weigh 5.0 +/- 0.1 mg of crushed reconstituted plant leaf and mix with 100.0 +/- 0.1 g of demineralized water, the resistivity of the demineralized water being of the order of 18 .2 Megohm/cm,
- magnetically stir the sample in water for 15 min at a temperature of 20°C,
- measure the pH.

The pH of the reconstituted plant leaf of the present invention may depend on the pKa of the organic acid. For example, the pH may be between 5.0 and 5.5 for an organic acid having a pKa less than or equal to 4. Alternatively, the pH may be between 5.5 and 6.0 for an organic acid having a pKa greater than 4.

For the purposes of the present application, the term "nicotine salt" designates a form of nicotine characterized by the interaction between nicotine in monoprotonated form and an organic acid in carboxylate form. The structure of nicotine is such that it includes two nitrogen atoms capable of accepting protons from the organic acid and, therefore, it can be present in neutral form (unprotonated form), in monoprotonated form and/ or in diprotonated form.

The total content by weight of nicotine dry matter in the reconstituted plant leaf may be from 0.1% to 4%, in particular from 0.5% to 3%, more particularly from 0.75% to 2.5%. .

Advantageously, the reconstituted plant leaf comprising nicotine in such ranges generates an aerosol which allows the user to obtain an experience similar to that provided by the aerosol generated by a conventional tobacco heating device and by a smoke generated by a burned tobacco product.

The nicotine:organic acid molar ratio may be from 1:0.1 to 1:10, in particular from 1:0.4 to 1:5, more particularly from 1:0.5 to 1:3.

Advantageously, the reconstituted plant leaf comprising the molar ratio in these ranges has a pH in the aforementioned ranges.

Typically, the organic acid can have:
a pKa less than or equal to 5, in particular less than 4, more particularly less than 3 and
a vapor pressure at 25°C of 10 ^{- 1 0} to 20 mmHg, in particular of 10 ^-8 to 10 mmHg, more particularly of 10 ^-8 to 1 mmHg, a boiling point greater than or equal to 300°C or both.

Advantageously, the organic acid having such a pKa and such a vapor pressure and/or such a boiling point:
- promotes the formation of nicotine salt in the reconstituted plant leaf of the present invention with a small quantity of organic acid,
- limits the transfer of organic acid into the aerosol generated by the reconstituted plant leaf of the present invention, thus limiting the acid taste of said aerosol, and
- limits the loss of acid during the manufacture of the reconstituted plant leaf of the present invention.

The organic acid can have several pKas. For example, a dicarboxylic acid has 2 pKa. In this case, the lowest pKa of this organic acid may be less than or equal to 5, in particular less than 4, more particularly less than 3.

The organic acid may be alginic acid, aspartic acid, benzoic acid, citric acid, fumaric acid, glutamic acid, glycolic acid, lactic acid, levulinic acid , malic acid, pectic acid, pyruvic acid, salicylic acid, tartaric acid, glucuronic acid, galacturonic acid, myristic acid or mixtures thereof, in particular benzoic acid , citric acid, fumaric acid, glycolic acid, lactic acid, levulinic acid, malic acid, pyruvic acid, salicylic acid or mixtures thereof, more particularly citric acid , fumaric acid, glycolic acid, malic acid, lactic acid, pyruvic acid, salicylic acid or mixtures thereof.

Advantageously, the organic acids in this list are for the most part natural-based products, do not alter the organoleptic properties of the aerosol and/or confer positive sensory properties.

For the purposes of the present application, the term "fibrous support" designates a base sheet consisting of plant fibers, in particular refined plant fibers. The base sheet is typically obtained by a papermaking process.

In the context of this application, the term “plant extract” designates all of the water-soluble products of the plant. Advantageously, the plant extract comprises compounds giving the aerosol organoleptic properties and/or therapeutic or well-being properties.

For the purposes of the present application, the term "aerosol-generating agent" designates a compound which allows the formation of an aerosol when heated.

For the purposes of the present application, the term "plant fibers" designates plant fibers having undergone a refining step allowing the fibrillation and/or cutting of the plant fibers. The refining step is conventionally implemented in a papermaking process, such as the papermaking process manufacturing reconstituted papermaking tobacco. On the other hand, the refining step is not implemented in a manufacturing process for cast leaf reconstituted tobacco.

For example, refined plant fibers may have a Schopper-Riegler degree (°SR) of 15°SR to 75°SR, in particular from 20°SR to 65°SR, more particularly from 25°SR to 55°SR.

Typically, the fibrous support may comprise fibers from the same plant or from several plants.

Typically, the content by weight of dry matter of the plant fibers included in the reconstituted plant leaf can be from 15% to 70%, in particular from 20% to 61%, more particularly from 30% to 57%.

Typically, the fibrous support of the reconstituted plant sheet may also comprise cellulose-based plant fibers.

Cellulose-based plant fibers are fibers obtained by a chemical or mechanical or thermo-mechanical cooking process, such as wood pulp, or annual plants such as flax for example. A mixture of these cellulose-based plant fibers can also be used.

Advantageously, these cellulose-based plant fibers can improve the mechanical strength properties of the reconstituted plant sheet.

Typically, cellulose-based plant fibers can represent from 0.5% to 20%, in particular from 3% to 17.5%, more particularly from 5% to 15% by weight of dry matter of the reconstituted plant leaf. , the remaining fibers of the reconstituted plant leaf being the plant fibers.

Let S _AG be the total content by weight of dry matter of the aerosol-generating agent included in the reconstituted plant leaf of the present invention. S _AG can be from 10% to 40%, in particular from 12% to 35%, more particularly from 15% to 30%.

S _AG may depend on organic acid. For example, S _AG being 15% to 20% is suitable for organic acid soluble in solvent, especially in water. S _AG being 20% to 30% is suitable for organic acid insoluble or poorly soluble in solvent, especially in water.

Aerosol generated from a reconstituted plant leaf having an S _AG greater than the ranges mentioned above causes an unwanted burn of the mouth and/or throat (a phenomenon known as "hot puff").

The volume of the aerosol generated from a reconstituted plant leaf having a S _AG below the ranges mentioned above is too small to be pleasant. This aerosol is also not in good taste.

The aerosol generating agent may be a polyol, a non-polyol or mixtures thereof. Typically, an aerosol generating agent that is a polyol may be glycerol, propylene glycol, sorbitol, triethylene glycol or mixtures thereof. An aerosol generating agent which is a non-polyol may be glyceryl diacetate, glyceryl triacetate, triethyl citrate, isopropyl myristate or mixtures thereof.

The aerosol generating agent may preferably be glycerol, propylene glycol or a mixture of glycerol and propylene glycol, with glycerol being preferred.

An aerosol is generated upon heating the reconstituted plant leaf of the invention. Advantageously, the plant extract which comprises aromatic compounds imparts aromas of the plant to this aerosol. By simply changing the reconstituted plant leaf, the user can easily vary the aromas of the aerosol generated by heating said reconstituted plant leaf.

The organoleptic properties and the therapeutic properties of the aerosol formed by heating said reconstituted plant leaf may depend on the content by weight of dry matter of the plant extract included in the reconstituted plant leaf of the present invention.

The total content by weight of dry matter of the plant extract depends on the plant used and, more particularly, on the content of aromatic compounds or compounds having therapeutic or well-being properties of the plant used.

Let S _p be the total content by weight of dry matter of the plant extract included in the reconstituted plant leaf of the present invention. S _p can be from 10% to 70%, in particular from 15% to 50%, more particularly from 20% to 35%.

Advantageously, an S _p included in these ranges of values makes it possible to generate, at a comfortable draft resistance, an aerosol having satisfactory organoleptic properties, that is to say having a constant high taste intensity and a constant higher volume.

To determine S _P , we can use the following method:
the reconstituted plant leaf to be analyzed is crushed to obtain a particle size less than or equal to 1 mm. The reconstituted plant leaf is then mixed with boiling water for 45 minutes to extract all of the plant extract. S _P is calculated by the difference between the dry weight of the reconstituted plant leaf sample to be analyzed and the dry weight of the fibrous residue after extraction.

The plant fibers and the plant extract can be independently obtained from a plant selected from spore-producing plants, seed-producing plants and mixtures thereof. In particular, the plant may be a plant chosen from food plants, aromatic plants, perfume plants, medicinal plants, and mixtures thereof.

If the plant is a medicinal plant, the aerosol generated by heating the reconstituted plant leaf may also have therapeutic properties such that the reconstituted plant leaf may be used for therapeutic treatment.

Advantageously, a plant extract obtained from a mixture of plants makes it possible to offer a wide range of organoleptic properties and/or therapeutic properties. A mixture of plants also makes it possible to counterbalance the unpleasant organoleptic properties of a plant in the mixture, for example a medicinal plant, with the pleasant organoleptic properties of another plant in the mixture, for example an aromatic plant or a perfume plant.

The plant fibers may be obtained from a first plant and the plant extract may be obtained from a second plant. Indeed, the fibers of a plant may not have mechanical properties allowing the formation of a fibrous support, but the extract of this plant can give the aerosol organoleptic properties and/or desired therapeutic properties. Conversely, the fibers of a plant may have mechanical properties allowing the formation of a fibrous support, but the extract of this plant may not confer on the aerosol the organoleptic properties and/or the desired therapeutic properties.

Advantageously, the mixture of plants to obtain the plant fibers makes it possible to adjust the mechanical properties of the reconstituted plant leaf and/or the organoleptic or chemical properties of the aerosol.

Typically, food plants are garlic, coffee, ginger, licorice, stevia, tea, cocoa, chamomile, mate, anise such as star anise (or star anise), green anise or their mixtures, fennel, lemongrass.

Typically, aromatic plants are basil, turmeric, cloves, bay leaf, oregano, mint, rosemary, sage, thyme.

Typically, perfume plants are lavender, rose, eucalyptus.

Typically, medicinal plants are those indicated in the document, List A of medicinal plants traditionally used (French Pharmacopoeia January 2016, published by the National Medicines Safety Agency (ANSM) or plants known to include compounds with therapeutic properties Typically, the medicinal plants listed are ginkgo, ginseng, sour cherry, peppermint, sweet mint, willow and red vine.

Typically, eucalyptus is one of the medicinal plants known to include compounds that have therapeutic properties.

Typically, the plant fibers and plant extract of the reconstituted plant leaf of the present invention may be derived from various plant parts, the plant parts being parts of the plant itself or the result of processing of various parts of plants. Typically, plant parts may be whole plant parts or debris from threshing or mixing and chopping plant parts. Plant parts may also be byproducts of extraction.

Typically, the plant parts can be chosen from the plant parts richest in aromatic compounds giving the aerosol its organoleptic properties. Typically, these parts may be the entire plant, the aerial parts of the plant, such as the flower bud, the bark of the branch, the bark of the stem, the leaves, the flower, the fruit and its peduncle, the seed, petal, flowering top, or underground parts, e.g. bulb, roots, root bark, rhizome, or mixtures thereof. The part of the plant can also be the result of the mechanical, chemical or mechano-chemical treatment of one or more parts of the plant, such as for example the shell protecting the cocoa bean resulting from the process of shelling the bean.

Among the food plants, garlic bulb, coffee cherry, star anise fruit, ginger rhizome, licorice root and stevia or tea leaves can for example be chosen as parts.

Among aromatic plants, we can for example choose the flower buds of the clove tree (cloves), the leaves of basil, bay and sage, the leaves and the flowering tops of mint, oregano, rosemary and thyme, or the rhizome of turmeric.

Typically, among perfume plants, the flower and flowering top of lavender, or the bud and petals of the rose flower may be selected.

Among the medicinal plants listed in the French pharmacopoeia, one can for example choose the gingko leaf, the underground part of ginseng, the peduncle of the sour cherry fruit (cherry stem), the leaves and flowering top of peppermint, the bark of the stem and the leaves of the willow, or the leaves of the red vine.

The plant may be an anise such as star anise, green anise or mixtures thereof, eucalyptus, fennel, ginger, mint, peppermint, licorice, sage, stevia or mixtures thereof, especially mint.

Alternatively, the density of the reconstituted plant leaf of the present invention may be less than 0.60 g/cm ³ , in particular from 0.20 g/cm ³ to 0.59 g/m ³ , more particularly from 0. 45 g/cm ³ to 0.58 g/cm ³ .

Advantageously, a density included in these ranges of values makes it possible to generate, at a comfortable draft resistance, an aerosol having satisfactory organoleptic properties, that is to say having a constant high taste intensity and a constant higher volume.

The density of the reconstituted plant leaf is calculated by dividing its weight by its thickness.

To determine the weight of the reconstituted plant leaf, the following method can be used:
a 0.25 m² sample is cut using a template (dimensions: 57.5 x 43.5 cm) approximately 15 cm from the edge of the reconstituted plant leaf to be analyzed. The sample is then folded into quarters and placed on a hot plate to dry to remove water without removing the aerosol-generating agent.
The dried sample is then weighed to determine the weight of the reconstituted plant leaf.

To determine the thickness of the reconstituted plant leaf, we can use the method described in standard NF EN ISO 534 (December 2011) adapted to reconstituted plant leaves:
- measurement of the average thickness of the control parchment paper used to measure the thickness of the reconstituted plant leaf (6 measurements minimum on a layer, on locations marked on the paper),
- the sample of reconstituted plant leaf is placed between 2 layers of baking paper,
- as soon as the micrometer probe is in place, wait 30 seconds before taking the measurement (stabilization of the sample when measuring thickness),
- 6 minimum measurements are taken at the locations marked on the sheet of baking paper,
- the thickness of the reconstituted plant leaf calculated is the average of the overall thickness measured (reconstituted plant leaf + 2 layers of parchment paper) from which 2 times the average thickness of the parchment paper is subtracted.

Typically, the reconstituted plant leaf may have a weight of less than 300 g/m², in particular from 20 g/m² to 250 g/m², more particularly from 80 g/m² to 200 g/m², even more particularly from 105 g /m² to 130 g/m².

Typically, the thickness of the fibrous support of the reconstituted plant leaf can be from 100 µm to 450 µm, in particular from 120 µm to 375 µm, more particularly from 140 µm to 325 µm, even more particularly from 180 µm to 250 µm .

There is also proposed a process for producing the reconstituted plant leaf of the present invention as defined above, comprising the following steps:
a) passing plant fibers through a paper machine so as to produce a base sheet,
b) formation of a solution comprising:
- plant extract,
- the aerosol generating agent, and
- nicotine and organic acid, or nicotine salt,
; c) bringing the solution into contact with the base sheet to obtain a moist reconstituted plant leaf, and
d) drying the wet reconstituted plant sheet to produce the reconstituted plant sheet.

The plant fibers, plant extract, aerosol generating agent, organic acid and nicotine salt are as defined above in relation to the reconstituted plant leaf of the present invention.

In the solution formed during step b), the nicotine:organic acid molar ratio can be from 1:0.1 to 1:10, in particular from 1:0.4 to 1:5, more particularly from 1 :0.5 to 1:3.

The fibrous media can be produced using a paper machine. Therefore, the reconstituted plant leaf of the invention can be a reconstituted plant leaf obtainable by a papermaking process.

The pH of the solution formed during step b) and occurring in step c) can be acidic, in particular from 4.0 to 6.5, more particularly from 5.0 to 6.0, even more particularly from 5.2 to 5.8.

Advantageously, a solution having a pH in these ranges allows the production of the reconstituted plant leaf of the present invention.

The pH of the solution depends mainly on the amount of acid, nicotine and/or nicotine salt in said solution. Those skilled in the art know how to adjust the amount of acid, nicotine and/or nicotine salt in the solution so that said solution has a pH in the above range.

The inventors noted that the pH and buffering capacity of the base sheet may depend on the plant type of the plant fibers. The pH of the solution can therefore be adapted to the pH and buffering power of the base sheet to allow the production of the reconstituted plant leaf of the present invention.

The pH of the solution is determined using a pH electrode. The pH of the base leaf is determined by the method described above determining the pH of the reconstituted plant leaf of the present invention.

Plant fibers and plant extract can be obtained according to the following steps:
e) mixing one or more parts of the plant with a solvent in order to extract the plant extract from the plant fibers
, f) separation of the plant extract from the plant fibers.

The plant extract and the plant fibers are therefore typically obtained by means of a dissociation process. In step e), one or more plant parts are mixed with a solvent, for example in a digester, in order to extract the plant extract from the plant fibers. During step f), the plant extract is separated from the plant fibers, for example by passing through a screw press, in order to isolate and obtain, on the one hand, the plant fibers and , on the other hand, the plant extract.

Typically, the solvent may be an apolar solvent, an aprotic polar solvent, a protic polar solvent or mixtures thereof, in particular the solvent may be methanol, dichloromethane, ethanol, acetone, butanol, water or their mixtures, more particularly the solvent is ethanol, acetone, water or their mixtures.

The solvent may be an aqueous solvent, more particularly the solvent is water.

Those skilled in the art know how to adapt the temperature of the solvent during step e) to the plant, the part of the plant and the parts of the plant to be treated. Typically, the solvent temperature during processing of a root or bark will be higher than the solvent temperature during processing of a leaf or petal.

Typically, the temperature of the solvent during step e) can be between 10°C and 100°C, in particular between 30°C and 90°C, more particularly between 40°C and 80°C.

Typically, plant fibers can be refined in a refiner and then involved in step a).

Typically, plant fibers can come from various plants.

The fibers of each plant can be obtained separately according to the dissociation process described above. They can then be mixed so that this mixture of fibers from different plants passes through the paper machine to form the fibrous support. It is also possible to obtain fibers from different plants together by joining one or more parts of the different plants and then subjecting them to the dissociation process described above. The water temperature will then be adapted to the plants to be treated and, in particular, to the plant requiring the highest water temperature for the extraction of the extract from this plant. This alternative embodiment is very advantageous because it makes it possible to obtain fibers from different plants without carrying out several dissociation processes in parallel.

Typically, the plant extract may be an extract of various plants.

The extract of various plants can be obtained by mixing various plant extracts obtained separately according to the dissociation method described above. It is also possible to obtain the extract of various plants by combining one or more parts of the various plants and then subjecting them to the dissociation process described above. The water temperature will then be adapted to the plants to be treated and, in particular, to the plant requiring the highest water temperature to extract the extract from this water-soluble plant. This alternative embodiment is very advantageous because it makes it possible to obtain the extract of various plants without carrying out several processes in parallel. In these two situations, extracts from various plants are involved in step b).

The solution can be formed during step b) by mixing in a solvent, in particular water, the organic acid, nicotine, the aerosol generating agent and the plant extract. As a result, the nicotine salt is formed in situ in the solution by reaction between the organic acid and nicotine.
The organic acid can be added to the solvent before the nicotine. In fact, it advantageously promotes the formation of nicotine salt.
This step b) is suitable for an organic acid soluble in the solvent of the solution, in particular in water.

Alternatively, the solution can be formed during step b) by mixing in a solvent, in particular water, the nicotine salt, the aerosol generating agent and the plant extract. Therefore, the nicotine salt can be formed ex-situ or can be purchased before being added to the solvent, particularly water.
This alternative to step b) is suitable for an organic acid that is insoluble or poorly soluble in the solvent of the solution, in particular in water. Such an organic acid is, for example, salicylic acid, benzoic acid or mixtures thereof.

Typically, various plant extracts, obtained according to the dissociation process described above, can also be added to the solution during step b).

Typically, the plant extract can be concentrated before being added to the solution during step b). A device such as a vacuum evaporation device can be used to concentrate the plant extract.

Typically, step c) can be carried out by impregnation or by spraying, in particular by impregnation. Typically, the impregnation can be carried out using a size-press.

Typically, drying step d) can be carried out by infrared ramp, American battery drying rollers, hot air drying in a tunnel dryer, a vertical dryer, a fluidized bed dryer, a pneumatic dryer, in particular in a tunnel dryer.

The reconstituted plant leaf produced in step d) can be shaped in particulate form, in the form of a creped sheet, in the form of scaferlatis.

The reconstituted plant leaf of the invention can be used in a heating device.

Thus, a consumable is also proposed for a device for heating tobacco without burning it, comprising a reconstituted plant leaf according to the invention as defined above.

For the purposes of the present invention, the term "consumable" designates the plant leaf reconstituted according to the invention as such, a sachet comprising the plant leaf reconstituted according to the invention, a capsule comprising the plant leaf reconstituted according to the invention or a stick for a heating device comprising the reconstituted plant leaf according to the invention.

For the purposes of this application, the term "device for heating tobacco without burning it" designates any device allowing the formation of an aerosol intended to be inhaled by a consumer. The aerosol replaces smoke, allowing the user to inhale the aromas of the plant while significantly reducing the user's exposure to harmful components. Throughout this application, the term "device for heating tobacco without burning it" can be replaced by the term "heating device".

The consumable is adapted to be introduced into a dedicated housing of the heating device, and those skilled in the art will know how to adapt the consumable according to the dedicated housing of the heating device.

The reconstituted plant leaf according to the invention, as a consumable, can be shaped so as to be adapted to the dedicated housing of the heating device. For example, it can be in particulate form, in the form of a creped sheet, in the form of scaferlatis, in particular in the form of scaferlatis having a width of 0.5 mm to 1 mm.

The bag can be made of paper with an interior volume and the reconstituted plant leaf according to the invention is contained in the interior volume. In the interior volume, the reconstituted plant leaf according to the invention can be shaped, in particular in particulate form, in the form of a creped sheet, in the form of scaferlatis.

The sachet may have a cylindrical shape with two sealed ends and a third seal connecting the two sealed ends.

Alternatively, the bag may comprise a first layer of paper and a second layer of paper:
- from two different sheets of paper that are sealed on all sides, or - from the same sheet of paper that is folded on one side and sealed on all other sides.

The paper in the sachet can be cigarette paper, rolling cigarette paper, plant fiber paper, in particular cigarette paper.

The reconstituted plant leaf according to the invention can, for example, be presented in particulate form in a sachet or in a capsule.

The reconstituted plant leaf according to the invention can in particular be in the form of scaferlatis in a stick for a heating device.

According to one embodiment, the reconstituted plant leaf included in the consumable may be obtainable by the process according to the invention as defined above.

It is also proposed to use a reconstituted plant leaf according to the invention as defined above or a consumable according to the invention as defined above in a device for heating tobacco without burning it.

Typically, a heating device comprises, in the direction of the air flow, an air inlet, a heating body, a housing intended to place and maintain the reconstituted plant leaf of the invention comprising the generating agent aerosol, and an air outlet intended to be introduced into the mouth of the user. The air inlet, the heating body, the housing and the air outlet are typically connected at least fluidly to each other.

Typically, when the heater is in use, air is drawn by the user into the heater via the air inlet; the sucked air then passes through the heated part so as to obtain heated air; upon contact with the reconstituted plant leaf of the invention comprising the aerosol generating agent, held in the housing, an aerosol is formed and is then inhaled by the user. If the plant is a medicinal plant, then the aerosol formed has therapeutic properties.

In addition, thanks to the heating device, there is no combustion of the leaf. The user can therefore benefit from the organoleptic properties of the plant and the effect of nicotine while significantly reducing their exposure to harmful components.

The reconstituted plant leaf according to the invention as defined above can also be used as a paper cape.

It is also proposed a non-therapeutic use of a consumable as defined above in a device for heating tobacco without burning it.

A consumable as defined above is also proposed for its use in a heating device for therapeutic purposes, the plant being chosen from medicinal plants.

Examples

Example 1: Manufacturing

Example 1A : the plant is mint gentle and the organic acid is acid levulinic .

A mixture of sweet mint leaves is brought into contact with water in the laboratory in a water bath at 85°C with manual stirring for 30 minutes. Sweet mint extracts are separated from sweet mint fibers by centrifugation.

Sweet mint fibers are passed through a laboratory paper machine to obtain a base sheet.

Sweet mint extracts are mixed with glycerol. An aqueous solution of nicotine and levulinic acid is prepared. The mixture of sweet mint extracts and glycerol and the aqueous solution are mixed to form a solution having a pH of 5.7.

The solution is added to the base leaf by impregnation in a sizing press so as to obtain, after drying, a reconstituted sweet mint leaf having a pH of 6.3.

In the reconstituted sweet mint leaf:
- the total content by weight of dry matter of:
- nicotine is 1.48%
, - sweet mint extract is 23.7%, and
- glycerol is 17.7%, and
- the nicotine:levulinic acid molar ratio is 1:1.28.

Example 1B: the plant is sweet mint and the organic acid is acid levulinic .

A mixture of sweet mint leaves is brought into contact with water in the laboratory in a water bath at 85°C with manual stirring for 30 minutes. Sweet mint extracts are separated from sweet mint fibers by centrifugation.

Sweet mint fibers are passed through a laboratory paper machine to obtain a base sheet.

Sweet mint extracts are mixed with glycerol. An aqueous solution of nicotine and levulinic acid is prepared. The mixture of sweet mint and glycerol extracts and the aqueous solution are mixed to form a solution.

The solution is added to the base leaf by impregnation in a sizing press so as to obtain, after drying, a reconstituted sweet mint leaf having a pH of 5.6.

In the reconstituted sweet mint leaf:
- the total content by weight of dry matter of:
- nicotine is 1.55%,
- sweet mint extract is 21.3%, and
- glycerol is 17.3%.
- the nicotine:levulinic acid molar ratio is 1:2.18.

Example 1 C : the plant is sweet mint and the organic acid is salicylic acid.

A mixture of sweet mint leaves is brought into contact with water in the laboratory in a water bath at 85°C with manual stirring for 30 minutes. Sweet mint extracts are separated from sweet mint fibers by centrifugation.

Sweet mint fibers are passed through a laboratory paper machine to obtain a base sheet.

Salicylic acid is mixed with glycerol to form a mixture. Nicotine is added to this mixture to form a second mixture. This second mixture is added to the sweet mint extracts to form an aqueous solution.

The aqueous solution is added to the base sheet by impregnation in a sizing press so as to obtain, after drying, a reconstituted sweet mint leaf having a pH of 5.5.

In the reconstituted sweet mint leaf:
- the total content by weight of dry matter of:
- nicotine is 0.97%
, - the sweet mint extract is 19.2%, and
- glycerol is 27.2%, and
- the nicotine:salicylic acid molar ratio is 1:2.8.

Example 1D: the plant is sweet mint and the organic acid is salicylic acid.

A mixture of sweet mint leaves is brought into contact with water in the laboratory in a water bath at 85°C with manual stirring for 30 minutes. Sweet mint extracts are separated from sweet mint fibers by centrifugation.

Sweet mint fibers are passed through a laboratory paper machine to obtain a base sheet.

Salicylic acid is mixed with glycerol to form a mixture. Nicotine is added to this mixture to form a second mixture. This second mixture is added to the sweet mint extracts to form an aqueous solution having a pH of 5.5.

The aqueous solution is added to the base sheet by impregnation in a sizing press so as to obtain, after drying, a reconstituted sweet mint leaf having a pH of 6.5.

In the reconstituted sweet mint leaf:
- the total content by weight of dry matter of:
- nicotine is 1.7%
, - sweet mint extract is 20.7%, and
- glycerol is 19.7%, and
- the molar ratio of nicotine: salicylic acid is 1:1.

Comparative example 1: the plant is sweet mint and no organic acid is added.

A mixture of sweet mint leaves is brought into contact with water in the laboratory in a water bath at 85°C with manual stirring for 30 minutes. Sweet mint extracts are separated from sweet mint fibers by centrifugation.

Sweet mint fibers are passed through a laboratory paper machine to obtain a base sheet.

Sweet mint extracts are mixed with glycerol. An aqueous solution of nicotine is prepared. The mixture of sweet mint extracts and glycerol and the aqueous solution are mixed to form a solution having a pH of 7.6.

The solution is added to the base leaf by impregnation in a sizing press so as to obtain, after drying, a reconstituted sweet mint leaf having a pH of 7.4.

In the reconstituted sweet mint leaf:
- the total content by weight of dry matter of:
- nicotine is 1.44%,
- sweet mint extract is 23.7%, and
- glycerol is 19.4%.

Example 2: Determination of nicotine release

Example 2A: Aging at high temperature

The reconstituted sweet mint leaves of Example 1A, Example 1B and Comparative Example 1 are stored for 11 days under the following conditions: 40°C, 60% relative humidity.

The total nicotine dry matter content by weight of the three samples is then measured by gas chromatography coupled to a flame ionization detector (GC-FID). The contents are presented in Table 1 below.

Example 1A Example 1B Comparative example 1 Initial nicotine content (%) 1.55 1.48 1.44 Nicotine content after storage (%) 1.42 1.27 0.83 % nicotine loss 8.4% 14.2% 42.4%

The results presented in Table 1 show that nicotine is stabilized in the reconstituted plant leaf according to the present invention having a pH between 4.9 and 7. The stabilization of nicotine is even better for the reconstituted plant leaf of the present invention. Example 1A.

Example 2B: Aging at room temperature

A sample of the reconstituted sweet mint leaf from Example 1C is stored for 11 days under the following conditions: 22°C, 60% relative humidity.

The total nicotine dry matter content by weight of the sample is then measured by gas chromatography coupled to a flame ionization detector (GC-FID). The contents are presented in Table 2 below.

Example 1C Initial nicotine content (%) 0.97 Nicotine content after storage (%) 0.97 % nicotine loss 0%

The results presented in Table 2 show that nicotine is stabilized in the reconstituted plant leaf of Example 1C according to the present invention.

Claims (15)

Reconstituted plant leaf comprising:
- a fibrous support comprising plant fibers,
- an aerosol-generating agent, and
- a plant extract,
in which the plant is not the tobacco plant,
characterized in that
it further comprises nicotine and an organic acid, or a nicotine salt, and
it has a pH of 4.9 to 7.0, especially 5.0 to 6.0. Reconstituted plant leaf according to claim 1, in which the organic acid has: a pKa less than or equal to 5, and
a vapor pressure at 25°C of 10 ^-10 mm to 20 mmHg, a boiling point greater than or equal to 300°C or both. Reconstituted plant leaf according to claim 1 or claim 2, in which the organic acid is alginic acid, aspartic acid, benzoic acid, citric acid, fumaric acid, glutamic acid, glycolic acid, lactic acid, levulinic acid, malic acid, pectic acid, pyruvic acid, salicylic acid, tartaric acid, glucuronic acid, galacturonic acid, myristic acid or mixtures thereof. Reconstituted plant leaf according to any one of claims 1 to 3, in which the total content by weight of nicotine dry matter is 0.1% to 4%. Reconstituted plant leaf according to any one of claims 1 to 4, in which the nicotine:organic acid molar ratio is from 1:0.1 to 1:10, in particular from 1:0.4 to 1:5, more particularly from 1:0.5 to 1:3. Reconstituted plant leaf according to any one of claims 1 to 5, in which the total content by weight of dry matter of the aerosol generating agent is 10% to 40%. Reconstituted plant leaf according to any one of claims 1 to 6, in which the total content by weight of dry matter of the plant extract is 10% to 70%. Reconstituted plant leaf according to any one of claims 1 to 7, in which the plant is chosen from food plants, aromatic plants, perfume plants, medicinal plants, and mixtures thereof. Reconstituted plant leaf according to any one of claims 1 to 8, in which the plant is anise, eucalyptus, fennel, ginger, mint, peppermint, licorice, sage, stevia or their mixtures. Process for producing a reconstituted plant leaf as defined in any one of claims 1 to 9, comprising the following steps:
a) passing plant fibers through a paper machine so as to produce a base sheet,
b) formation of a solution comprising:
- plant extract,
- the aerosol generating agent, and
- nicotine and organic acid, or nicotine salt,
c) bringing the solution into contact with the base sheet to obtain a moist reconstituted plant leaf, and
d) drying the wet reconstituted plant sheet to produce the reconstituted plant sheet. A method according to claim 10, wherein the pH of the solution is acidic. Method according to claim 10 or claim 11, in which, during step b), the solution is formed by: - mixing in a solvent, the organic acid, nicotine, the aerosol-generating agent and the plant extract, or - mixing in a solvent, the nicotine salt, the aerosol generating agent and the plant extract. Consumable for a device for heating tobacco without burning it, comprising a reconstituted plant leaf as defined in any one of claims 1 to 9. Non-therapeutic use of a consumable as defined in claim 13 in a device for heating tobacco without burning it. Plant extract for its use in a heating device for therapeutic purposes, the plant being chosen from medicinal plants and the plant extract being included in a consumable as defined in claim 13.