CA1089697A - Sugarless coating for food products - Google Patents

Abstract

Abstract of the Disclosure A sugarless coating composition for food products such as cereal based ready-to-eat foods comprising a blend of a white pyro-dextrin, an edible oil- or'fat-derived oleaginous material and, optionally and preferably, a sugarless sweetener, said composition being free of mono- and disaccharides and other low molecular weight polysaccharide sweeteners and having a low dextrose equivalent value (D.E.), preferably of not more than 10Ø The coating may be prepared as a syrup containing the above ingredients and water and then applied to a food product, e.g., prepared cereal product par-ticles, and dried.

Description

..11 , ~96~37 Hackground o~ the Invention Field of the Invention ._ _ . .
The present invention relates generally to coatings and syrups for preparing food compositions such as cereal based ready-to-eat food products and to the resultant coated food compositions.
ore particularly, the present invention relates to a novel sugar-less coating for food compos~tions, e.gO~ prepared cereal products uch as dry breakfast cereals and the like in a characteristic toasted, fried and/or expanded or i'puffed" form, having a character-istic flavor depending on the cereal grain source and which may bere-sweetened if desired, to a method of preparing the coated prod-uct and to the resultant coated food products, e.g., coated cereal products. The present invention also relates to a syrup suitable for providing said coating.
Description of the Prior Art : ..
Pre-sweetened food compositions such as ready-to-eat cereals comprising a prepared cereal product coated with a composi-tion essentially containing a natural sugar such as sucrose and/or corn syrup are well known to the art. Recently, due partly to un-precedented increases in price for natural sugar sources and partlyto consumer demand for cereal and other food products of higher nutrition containing little or no added natural sugar, attempts have been made to provide food compositions such as cereal products hich are free o~ sucrose and other natuxal sugars and which may or may not be pre-sweetened. However, these prior art attempts have failed to provide coatings for food compositions, e.g., cereal pro~
ucts, having the flavor and textural characteristics of conventional .~
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coatings such as those containing natural sugars. -It is therefore a primary object of the present invention to ~rovide a sugarless composition suitable for use as a coating on a prepared food composition such as a cereal product which overcomes the disadvantages of prior art coatings.
SUMMARY OF THE INVENTION
Thus, the present invention provides a sugarless coating composition for a foodstuff comprising a blend ~ -10 containing from 70 to 98 parts by weight of a highly converted sugarless white pyrodextrin having a dextrose equivalent value of not more than 10.0 and from 2 to 30 parts by weight of an edible oil- or fat-derived oleaginous material, each weight percentage being on a dry basis per 100 parts by weight of coating composition, said composition being free of mono- and disaccharides and other low molecular weight polysaccharide sweeteners and having a dextrose equivalent value of not more than 10.0, said oleaginous material being in or near the solid state ~-at normal foodstuff storage temperatures. Optionally and preferably, the composition contains also a sugar-less sweetener and may contain other ingredients including flavoring agents, coloring agents and vitamins.
The coating may be prepared as a syrup containing the above essential ingredients, with or without said sugarless sweetener, and other ingredients together with .. . .

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sufficient water to provide a syrupy consistency and then applied to a food composition such as prepared cereal product particles by any conventional method including those used for preparing cereal products with a sugar based coating. The coating of the present invention has excellent gloss and its film-forming properties enable it to cover up to the entire surfaces of the cereal product particles using relatively low levels of coating. The finished and coated cereal based food composition remains crisp in milk longer than conventional sugar coated cereals. In addition, the high cereal base/coating ratios permit the preparation of cereal products having high nutrional values, i.e., higher protein.
As used herein, the term "prepared cereal product"
refers to any of the wide variety of proteinaceous, ; toasted, fried and/or "puffed" cereal particles and . , ~ .
includes any of the wide variety of dry, cereal yrain based food products available commercially such as, for ~` example, corn flakes, puffed corn, toasted oat cereal, toasted rice cerel, puffed rice, toasted rice, whole bran cereal, whole bran cereal with wheat germ, bran flakes, wheat flakes, puffed wheat, shredded wheat, wheat germ, French fried noodles, French fried corn meals, and mixtures or combinations thereof. Known protein fortifiers such as soy flour can also be employed in the course of preparation of the cereal ~
constituent, if desired. Although the ;

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~)89~t7 preferred food composition is a prepared cereal produc-t, other food compositions may be coated with the compositions of the present in-vention.
Description of the Preferred Embodiments The term dextrin as known to the art and used herein gen-erally refers to products produced by the dry heating or roasting (pyrolysis) of unmodified starches to produce products known as pyrodextrins or torrefaction dextrins. However, the term dextrin is sometimes interpreted to,include products that result from con-0 trolled hydrolysis of starch~by certain enzymes or by controlied ~-acid-catalyzed hydrolysis of wet starch. These include the crys-talline Schardinger dextrins, residual or limit dextrins produced by liquefying or saccharifying enzymes, and certain oligosacchar-ides from wet-acid hydrolysis, such as those that are present in some corn syrups. -~ Although superficially simple, dextrinization produces fundamental changes in molecular structure that lead to complex mixtures of products. The primary reactions are believed to be (1) hydrolytic cleavage of the starch molecule, resulting in the ~ ;
`0 formation of lower molecular weight, more water soluble compounds;

(2) transglucosylation, leading to the formation of more highly branched molecules with little net change in molecular weight; and ; (3) some repolymsrization or condensation of the smaller molecules, particularly during the manufacture of highly converted products.
In the hydrolysis (wet) processes, the hydrolytic cleava~e reaction (l) above is a predominating reaction normally producing large amounts of lower molecular weight reducing carbohydrates. On the other hand, translgucosylation is an important reaction in py-rodextrinization. It is believed to be an intermolecular exchange 0 in whlch some of the predominant ~-D-(l-:~ 4) glucosidic linkages of _5_ ,. ' ,' ':

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l~B9697 native starch are changed to ~-D-(l-- 6) linkages. Thus, while hy-drolysis tends to produce more reducing groups, transglucosylation and repolymerization lower the number of reducing groups, and re-polymerization also tends to increase the molecular weight.
Pyrodextrins (torrefaction dextrins) are prepared by heat ing dry starch usually in the presence of small amounts of an acid catalyst. Occasionally, an alkaline catalyst or, rarely, an oxi-dizing agent is used. A large number of products can be prepared that, depending on conditions of manufacture, range in color from 0 white to tan, have low -to high solubilities in water, and afford pastes or solutions of low to medium viscosities. In general, these products are more soluble than is the parent starch and have lower viscosities, higher reducing powers, and different adhesive characteristics.
A large number of dextrin grades and types can be manu-~factured by controlling the starch source, moisture, catalyst, tem-perature, and duration of roasting, which are the variables in the process. It has become common practice to classify pyrodextrins into three primary categories, i.e., white pyrodextrins, yellow or `0 canary pyrodextrins, and British gums.
White pyrodextrins are prepared by mildly heating starch, ; , i.e., at 79-121C. for from 3 to 7 hours, with an acidic catalyst, such as hydrochloric acid, acetic acid, trichloroacetic acid or hypochlorous acid. Because this can he done in the presence of relatively large amounts of acid, conversion is rapid even at com-paratively low temperatures. Thus, color remains light, and the water solubility can be varied from low (short conversion time and/or low temperature) to high (longer cooking times at higher temperatures). Yellow or canary pyrodextrins are prepared by heat-ing starch with acid at higher temperatures (149-190) and for .~ . ' -6- ~
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generally longer times (6-20 hours) than are used for white pyro-dextrins. As a rule, these dextrins are over 95% soluble and can be used at concentrations of about 60~. British gums are prepared by heating starch at 135-190C. for 10-24 hours without added acid. The conversion is catalyzed by the traces of acids naturally present in the starch (or formed during pyrolysis) or by alkaline materials such as sodium carbonate, sodium bicarbonate, and ammoni In general, the products have dark colors, a wide range of cold water solubilities, and high viscosities.
In the present invention only white pyrodextrins are used The starches which may be used to form the white pyrodextrins in-clude tapioca starch, potato starch, sago starch, corn starch, wheat starch and other vegetable, cereal and root starches. The white pyrodextrins used in the present invention are the more high-ly converted, and thus more water soluble, products. A particular-ly preferred pyrodextrin is a highly converted white dextrin made by heating starch at temperatures in excess of 100C. for approxi-mately seven hours.
Another important characteristic of the white pyrodextrins useful in the coating compositions of the present invention is that they have a low dextrose equivalent value (D.E.), preferably of not more than 10.0, more preferably of not more than 5.~ and most pref-erably of not more than 3~0 so that the coating composition also has a low D.E. D.E. is defined as the amount of reducing groups expressed as dextrose and calculated as a percentage of the dry substance. The key phrase in the definition is "expressed as dex-trose". In other words, reducing yroups are being assayed, and the expression of results is in terms of a standard reducing sugar, dextrose. ~
As to the definition of "reducing sugar", tle term ~ ~;

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96~7 "reducing" refers to the chemical reaction of the aldehyde group found in many carbohydrates with mixtures of mild oxidizing agents such as copper. Carbohydrates that do not possess a free aldehyde group are termed non-reducing. Ir. fact, this reaction is the basis of the Dextrose Equivalent Assay. In general terms the reaction is as follows:
RCHO ~ 2 Cu~OH)2 ~ ~ RCOOH + Cu20 ~ 2H20 Although other chemical moieties present in carbohydrates and some organic materials other than aldehydes will undergo this oxidation, 0 only the reaction of aldehyd~s is important in calculating D.E.
since this is virtually the exclusive reducing group present in starch and starch reaction products such as dextrins. As to the term "sugar" in "reducing sugar", in this context sugar has no sweetness connotation whatsoever and refers to any type of carbo-hydrate including monosaccharides, oligosaccharides and poly-saccharides such as starch. This particular definition of sugar is familiar to those skilled in the art.
It is possible to treat starch by the pyrolytic or wet conversion processes and obtain dextrins having low D.E. values.
0 It has been found, however, that the wet processed dextrin will tend to have a high viscosity at relatively high solids concentra-tions in water~ On the other hand, the highly converted white pyro-dextrins have a low viscosity at relatively high solids concentra-tions, thus allowing for improved cladding properties at lower coating levels when using the highly converted white pyrodextrins in coating compositions such as those of the present invention.
~ As to the extent of conversion in reference to dextrins, if the pyrolysis of the starch is conducted at the higher end of the pertinent temperature range as discussed above and/or extended : ~

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~089697 ~¦to the hi er end Oe the pertinent reaction time r~nge, the re~lt-¦
ing product will be "highly converted". A highly converted wet process dextrin will have a high D.E. hecause of the nature of the hydrolysis reaction. On the other hand, the number of reducing groups or D.E. of a highly converted pyrodextrin does not necessar-ily increase and this is because of the strong influence of the transglucosylation and repolymerization mechanisms in pyrodextrin-ization.
The white pyrodextrins used in the coating compositions of the present invention as iwell as the resulting coating composi-tions are considered to be "sugarless", i.e., free of mono- and disaccharides and other low molecular weight polysaccharide sweet-eners. The sugarless white pyrodextrins used in the present in-vention comprise the reaction mixture produced from the pyrplysis of starch which when dissolved in water has a low viscosity com-pared to the original starch and no significant sweetening effect.
Desirably, the white pyrodextrins employed in this invention should be highly soluble and have a low viscosity at concentrations of 50% to 60% by weight in water. At a 50% concentration the viscos-ity should be in the range of 300-500 centipoise at 25C.
The edible oil- or fat-derived oleaginous materials are :' used in the coating of the present invention in an amount sufficien to tenderize the dextrin coating by breaking up the conventional substantially hard and brittle dextrin film. Suitable such oleag-inous materials include edible vegetable oils or fats such as co-conut oil, soybean oil, palm kernel oil, cottonseed oil and the like, or semi-solid materials containing edible fats or oils such as oleomargarine, unsweetened chocolate, etc. Other vegetable oils and fats which may be used lnclude corn oil, sunflower seed oil, :0 cocoa butter, olive oil and the like, or mixtures thereof.
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~ 9697 Hydrogenated vegetable oils of the above types may also be used.
Also suitable are such edible animal-derived fats such as butter and lard. Certain factors such as flavor acceptability, aroma and keeping qualities of the final product are to be considered when deciding upon the type of edible oleaginous material to be used.
For example, the fact that in the manufacture of ready-to-eat cereals, a shelf life of about nine months under average humidity and temperature conditions is sought, could effectively exclude or limit the amount which may be used of certain types of edible oils or fats such as fish or other marine oils of various types. Pre-ferably the oleaginous material is one that will be in or near the solid state at normal storage temperatures, the factor under con-sideration being to avoid any seepage from the coated cereal prod-uct even in the presence of the dextrin. Another consideration is a satisfactory "mouth feel" upon eating so that when a solid fat is used, the melting point should preferably be in the range of from about 70 to about 110F.
Any sugarless sweetener may be used in the coating com-positions of the present invention when a pre-sweetened product is desired. A preferred group of sweeteners are those derived from L-aspartic acid, e.g., Aspartame and sweet dipeptides described in U. S. Patent Nos. 3,492,131; 3,475,403 and 3,801,563. Other suit-able such sweeteners include cyclamate (N-cyclohexylsulfamic acid) and saccharin (2,3-dihydro-3-oxobenziosulfonazole). Pharmacolog-ically acceptable salts of cyclamate and saccharin can also be used and are preferred since they are more readily soluble. Suitable ~;
salts include the sodium, potassium, calcium, ammonium and magnes-ium salts The sodium salts are to be avoided where the sweetening composition is intended for use by diabetics or others on low . . .': ~' ''-' ~; "
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~CJI!~19~i97 sodium diets. Mixtures of the above sweeteners may be used, if desired, as may other such sugarless sweeteners. In general, any nutritlve and/or non-nutritive sweetener which is sugarless may be used.
The white pyrodextrin may be used in the coating composi-tion of the invention in an amount of from 70 to ~8 parts by weigh~
preferably from ~5 to 90 parts by weight, and the oleaginous mate-rial may be used in an amount of from 2 to 30 parts by weight, pre-ferably from 2 to 15 parts by weight and most preferably from 5 to 0 15 parts by weight, each on ~a dry basis, in 100 parts of coating composition. The proportion of sugarless sweetener present when employed is selected to obtain the desired sweetness and will vary considerably depending on the type used. Desirably, the pre-sweetened product may have a sweetness corresponding to convention-al sugar based coatlngs, e.g., cereal coatings. When the composi-tion is formulated as a syrup, water is added to the dry ingred-ients in an amount sufficient to provide a syrupy consistency.
Typically, 1 part by weight of dry ingredients is mixed with from 0.8 to 1.6 parts by weight, preferably from 1.0 to 1.2 parts by -~
~0 weight, of water.
Other ingredients such as vitamins, minerals, coloring and flavoring agents may be added to the coating composition of the present invention and the flavoring agents are particularly desired when the coating does not contain a sugarless sweetener.
The flavoring and coloring agents may be any of those of natural or synthetic origin which are acceptable for food use and are cer-tified for use by governmental authorities. For example, artificial food colors used are F D & C certified food colors or blends there-of. The flavoring and coloring agents may be added in amounts nec-0 essary to yield the intensity of flavor and color desired or, of :, . . :' , . , . . ; ~

~ 1089~97 course, may be omitted entirely. In addition, various vitamins ~ -: and minerals in prescribed amounts may be added to the compositions of the present invention.
In the preparation of the coating composition, the dry ingredients are blended with water and, if necessary, heated to above the melting point of the oleaginous material, e.g., from 100 to 175F. Preferably, the dextrin and sweetener, when used, are preblended and added to the water with agitation. The mixture is then, if necessary, heated to above the melting point of the O oleaginous material used and~the oleaginous material ~and flavor-ing and other ingredients, if used) is blended in. The coating composition is then applied to the foodstuff such as base cereal particles by any conventional method and the coated product is dried at a temperature of from 175~ to 225F. for from 45 to 90 minutes to a moisture content below 5.0%, preferably of from 2.0~
to 3.0%- :
There are two primary conventional methods of applying sucrose type coatings to cereals, and they may be used in applying the coating composition of the present invention. The first method O produces a hard transparent or candy-like g~aze and is described in U. S. ~atent Nos. 3,318,706 and 2,868,647. Sucrose is dissolved ~
with a small amount of corn or invert syrup (15-40%) in water to ;
give an 80% by weight solution. This solution is heated at 320-325F. until all but 1% of the water is evaporated, then is applied to the cereal bodies. The second method, which is well known to those skilled in the art, produces a frosted coating. An 80% su- -crose solution is heated to 200-215F., then is cooled to 140- ;
liOF. and applied continuously to cereal bodies in a tumble coater rhe coated cereal is conveyed to a dryer where the moisture content is reduc to ~-4%.

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The coating of the present invention may also be applied to the cereal based product by spraying or dipping methods and the coated cereal particles may be dried, for example, in trays in a forced draft oven, in a tumbler dryer, in a vertical swept tray .. , .............................................. . .. .. __ dryer (Wyssmont~ ), in a foraed hot air bed conveyor tNational~
etc.

The excellent film-forming property of the coating and syrup of the present invention enables the use of relatively low levels of coating. The cereal product base to syrup ratio will generally be between 10:3 and lO:S, typically 10:3.3. After coat-ing and drying, the base to coating ratio is between 8:1 and 4:1, typlcally 7:1.
Example 1 IngredientsParts by Weight White tapioca pyrodextrin 400 Vegetable shortening 40 Water 440 Aspartame 4 ; Flavor 2 Color As desired ------- ---The white tapioca pyrodextrin (K-Dex 4480 ~, National Starch Company) and sweetener (Aspartame~ ~ were preblended dry and added slowly to the water under agitation.
The mixture was heated to 160F. and the shortening and flavor (Dragoco Strawberry ~) were blended in. The resultant coating syrup was applied to base cereal puffs in a cereal base to syrup ratio of 10:4.4. The coated puffs were dried on a tray at 200F. in a forced hot air oven for approx-imately 1 hour to a moisture content of 3~. The cereal base to coating ratio of the dried coa-ted cereal puffs was 4 ' - ., . : , , .: , : , ,, . . , . , : , . : . . .

~ 3L~ 69';1 Composition oE Base Cereal Puffs Ingredients Parts b~_Weiqht Corn flour 100 Wheat flour 71 , Rice flour 41 Sugar 32 Monoglycerides 0.7 Example 2 ~ ~-Ingredients Parts by Weight 0 White -tapioca pyrodextrln 400 92 Soybean oil 40 Water 440 Flavor As desired Color As desired The white tapioca pyrodextrin was added to the water unde ~gitation. The mixture was heated to about 100F. and the soybean oil and any desired flavor and color were blended in. The result- -ant coating syrup was applied to corn flakes in a cereal to syrup ratio of 10:3.3. The coated flakes were dried on a tray at 200F.
,0 in a forced hot air oven for approximately one hour to a moisture content of 3~. The cereal base to coating ratio of the dried coat-ed corn flakes was 6:1.
Example 3 Ingredients Parts by Weight White tapioca pyrodextrin 400 76 Cottonseed oil 55 Water 440 Flavor As desired Color As desired . ~ ' ' , . '.' ~14-.

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The white tapioca pyrodextrin, cottonseed oil and any desired flavor and color were blended as in Example 2. The result-ant coating syrup was applied to spoon-sized shredded wheat in a cereal base to syrup ratio of 10:3.3. After drying as in the pre-ceding example, the cereal base to coating ratio of the dried coat-ed shredded wheat was 6~

Examples 4 and 5 ,- .
~ xamples 2 and 3 were repeated with the exception that the white tapioca pyrodextrin was replaced by equal amounts of a white corn pyrodextrin (Stadex 60K~ , A.E. Staley Manufacturing Co.) and the results were comparable.

One or more of the sugarless sweeteners described above may be added to the coating syrups of Examples 2~5 in amounts suf-ficient to supply the desired sweetness. When saccharin is~used as the sweetener, a small amount of sodium citrate is also usually added to mask or minimize any bitter taste of the saccharin in a manner well known to those skilled in the art.
All of the coating compositions of the present invention comprise a blend of ingredients whether or not a sugarless sweeten- -er is used.
While in the preceding examples the coating compositions have been applied to cereal based products, it will be apparent that the coatings may be applied to other foodstuffs in a manner known to the art. For example, the coatings may be applied to dietetic candies and cookies, to replace the conventional sugar-based coatings and icings. Chewing gums, and particularly dietetic chewing gums, may also be coated with the compositions of the pres-ent invention. With these other foodstuffs, the coating composi-tion will ordinarily be applied to only a portion of the surface 30 Of the product in a manner known to the art. ~;~

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~ 6g7 . The dextrose equivalent value (D.E.) of the white pyro . dextrins used in the present invention may be calculated by several commonly used methods for the estimation of aldose-type reducing groups. One such method is Me-thod ~-26 from Standard Analytical Methods of the Member Companies of the Corn Industries Research Foundation, Inc. .
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Claims (11)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A sugarless coating composition for a foodstuff comprising a blend containing from 70 to 98 parts by weight of a highly converted sugarless white pyrodextrin having a dextrose equivalent value of not more than 10.0 and from 2 to 30 parts by weight of an edible oil- or fat-derived oleaginous material, each weight percentage being on a dry basis per 100 parts by weight of coating composition, said composition being free of mono- and disaccharides and other low molecular weight polysaccharide sweeteners and having a dextrose equivalent value of not more than 10.0, said oleaginous material being in or near the solid state at normal foodstuff storage temperatures.

2. The composition according to claim 1 containing also a sugarless sweetener.

3. The composition according to claim 1 wherein said white pyrodextrin is formed from tapioca starch.

4. The composition of claim 1 wherein said white pyrodextrin is formed from corn starch.

5. The composition of claim 1 wherein water is present in an amount of from 0.8 to 1.6 parts by weight per 1 part by weight of dry ingredients.

6. A food composition comprising a foodstuff having at least a portion of the surface thereof coated with the composition of claim 1.

7. The food composition according to claim 5 wherein said foodstuff is a prepared cereal product.

8. A pre-sweetened food composition comprising a food-stuff having at least a portion of the surface thereof coated with the coating composition of claim 1.

9. The pre-sweetened food composition according to claim 8 wherein said foodstuff is a prepared cereal product.

10. A process for the preparation of a coated food composition which comprises applying to at least a portion of the surface of a foodstuff the composition of claim 5 and drying the coated foodstuff at a temperature and for a time sufficient to reduce the moisture content of said coated foodstuff to below 5% by weight of said foodstuff.

11. The process according to claim 10 wherein said foodstuff is a prepared cereal product.