CHEWING GUM CONTAINING SWEET PROTEIN AND SALT

Abstract: A chewing gum composition containing sweet protein and salt and having enhanced flavor. The sweet protein and salt are substantially physically separate in the chewing gum. The physical separation prevents the salt from suppressing the flavor and sweetness properties of the sweet portion. The salt is selected from sodium chloride, potassium chloride, or mixtures thereof. The salt is preferably present in the chewing gum in amounts between about 10 to about 1000 parts per million (ppm) by weight of the chewing gum. Various manufacturing methods for maintaining a substantial physical separation in the chewing gum are also provided.

Description: CHEWING GUM CONTAINING SWEET PROTEIN AND SALT BACKGROUND OF THE INVENTION This invention relates generally to chewing gum and in particular to chewing gum containing sweet protein. Chewing gum generally comprises chewable gum base, flavor, and a sweetener. Recently, the sweetness and flavor characteristics of chewing gum have been improved by using high intensity artificial sweeteners which have desirable organoleptic qualities. Further, these artificial sweeteners are non-cariogenic and nontoxic. High intensity sweeteners of recent interest for use in gums include aspartame, acesulfame K, cycla- ates, saccharin, sucralose, thaumatin, and monellin. Though most high intensity sweeteners currently known release relatively quickly from chewing gum, some, such as thaumatin, monellin, and like sweet proteins, do not completely release from the chewing gum upon salivation or during chewing. As a result, the flavor and sweet¬ ness of these high intensity sweeteners is not fully experienced. Thaumatin is a proteinaceous substance ob¬ tained from the fruit of the tropical plant Thaumato- coccus daniellii which grows in tropical Africa. Thaumatin is about 2,000 to 3,000 times sweeter than - 2 - sucrose and is known to have a lingering sweet after¬ taste. The sweet protein monellin, obtained from the fruit of the tropical plant Diosocoreo-plyllum cumminsii, has taste properties similar to thaumatin. Thaumatin and monellin, apart from their intense' sweetness, are recognized as high-potency flavor and sweetness adjuvants capable of potentiating sweetness and flavor in chewing gum compositions. See, for example, U.S. Patent No. 4,412,984 (van der Loo et al.) and U.S. Patent No. 4,228,198 (Burge et al.). Unfortunately, thaumatin and monellin are expensive and, when mixed with gum base and other ingredients, must be present in substantial amounts before a noticeable flavoring or sweetness can be achieved. These sweet proteins are known to be further suppressed when allowed to interact with ionic type ingredients such as salt. It is theorized that the sweet protein tends to become bound up in the gum base when mixed directly with the base or is denatured (i.e. experiences a reduced sweetening and/or flavor affect) when interacted with a salt, resulting in a reduction of their flavor and sweetness potentiating properties. Chewing gums, containing high intensity sweet proteins and salt which have enhanced flavor would therefore constitute an advance in the art. These gums would be readily accepted by the consuming public and enjoy commercial success. It is therefore an object of the present invention to provide chewing gums containing high intensity sweet proteins and salt which have enhanced flavor. It is another object of the present invention to provide a method of manufacturing chewing gum con¬ taining high intensity sweet proteins and salt which have the flavor characteristics mentioned above. These and other objectives will become apparent in light of the following specification. It is to be understood, however, that the above-mentioned objectives are not to be considered a limitation of the present invention, the scope of which is delineated in the appended claims. SUMMARY OF THE INVENTION According to the present invention there is provided a chewing gum composition having enhanced flavor. The composition comprises chewing gum ingredients such as a chewable gum base and flavor, sweet protein, and salt selected from sodium chloride, potassium chloride, or mixtures thereof. The sweet protein is physically separated from the salt in the gum. The sweet protein and salt do not substantially interact before the gum is chewed. The salt is preferably present in the chewing gum in amounts between about 10 to about 1000 parts per million (ppm) by weight of the chewing gum. In accordance with another embodiment of the present invention there is provided a method of manu¬ facturing chewing gum having enhanced flavor comprising chewing gum ingredients such as chewable gum base and flavor, sweet protein, and a salt selected from sodium chloride, potassium chloride, or mixtures thereof. The method comprises adding the sweet protein and salt to the chewing gum ingredients in a form such that the sweet protein and salt are physically separated in the gum and accordingly do not substantially interact before the gum is chewed. Preferably the salt is com¬ bined in an amount to yield between about 10 to about 1000 ppm by weight of the chewing gum. DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS According to the present invention it has now been discovered that the combination of salt and sweet protein as contemplated herein provide a chewing gum composition having enhanced flavor. By keeping the sweet protein and salt physically separate in the chewing gum during storage, the salt is prevented from interacting with the sweet protein. Thus, longer shelf life is also achieved. Sweet proteins contemplated by the present invention include thaumatin, monellin, and other high intensity sweet proteins having similar release charac¬ teristics. Accordingly the present invention con¬ templates high intensity sweet proteins having a low release when mixed with other ingredients. Though a precise method for determining the release charac¬ teristics of thaumatin and monellin is not presently known; it is believed that the high intensity sweet proteins contemplated have less than about 20% by weight release from a gum after about ten minutes of chewing when admixed directly in their normal form. As used herein, the term ιr normal form" is intended to mean the form in which the sweet protein is normally added to chewing gum ingredients. The form may thus be liquid or powder, but most likely will be powder. Preferably, thaumatin and monellin are con¬ templated. It is to be understood, however, that other sweet proteins not specifically mentioned herein may also be employed in the present invention. Further¬ more, any combination of these high intensity sweet proteins may also be employed. According to the present invention, sweet proteins comprise between about 5 and about 1000 ppm by weight of the chewing gum. Preferably, sweet proteins comprise between about 40 and about 600 ppm by weight of the chewing gum. It should be understood, however, that the release characteristics of sweet protein vary with the method of manufacture of the chewing gum em¬ ployed. For example, when the sweet protein thaumatin is added to other chewing gum ingredients in the powdered form, the chewing gum preferably comprises between about 100 and about 1000 ppm and more prefer¬ ably between about 500 and about 600 ppm by weight of the chewing gum. When applied to a chewable core center or combined as an emulsion, the chewing gum preferably comprises between about 5 and about 200 ppm and more preferably between about 75 and about 125 ppm by weight of the chewing gum. Finally when combined with a liquid center fill, the chewing gum preferably comprises between about 5 and about 100 ppm and more preferably between -about 40 and about 60 ppm by weight of the chewing gum. The salt contemplated by the present in¬ vention may comprise sodium chloride, potassium chloride, or mixtures thereof. It is contemplated that the salt be of a food grade quality. The salt may be obtained from any commercial manufacturer or may be processed by any of the methods known to those skilled in the art. According to the present invention, the chewing gum comprises the salt in amounts between about 10 and about 1000 ppm by weight of the chewing gum. Preferably, the chewing gum comprises salt in amounts between about 30 and about 100 ppm and most preferably between about 50 and about 80 ppm by weight of the chewing gum. The chewing gum however should not contain salt in amounts greater than about 1000 ppm because this is the point where it is believed that the perception saltines by the consumer occurs. It is to be understood that this perception level may vary depending upon the type and strength of flavor em¬ ployed, the level of sweetness, and the perception of other ingredients in the chewing gum. In general, mild flavors such as mild fruits and various mild mint flavors may be combined with up to 1000 ppm salt in chewing gum before saltiness is perceived by the consumer. Strong flavors, especially strong fruit flavors, in combination with acids and cinnamon type flavors may be combined with slightly higher amounts of salt without a saltiness perception by the consumer. It is believed that compositions containing acesulfame-K or fructose may possess a lower level of salt perception, possibly about 900 ppm. In any event, the chewing gum of the present invention preferably comprises salt in an amount below the salt perception level which is determined by the particular combination of the chewing gum ingredients. It is presently believed that this perception level is about 1000 ppm by weight of the chewing gum. In general, a chewing gum composition com¬ prises a water soluble bulk portion and a water insoluble chewable gum base portion and, typically water insoluble flavors. The water soluble portion dissipates with a portion of the flavor over a period of time during chewing. The gum base portion is re¬ tained in the mouth throughout the chew. The insoluble gum base generally comprises elastomers, resins, fats and oils, waxes,, softeners and inorganic fillers. Elastomers may include polyiso- butylene, isobutylene-isoprene copolymer, styrene butadiene rubber as well as natural latexes such as chicle. Resins include polyvinylacetate and terpene resins. Fats and oils may also be included in the gum base, including tallow, hydrogenated and partially hydrogenated vegetable oils, and cocoa butter. Com¬ monly employed waxes include paraffin, microcrystalline and natural waxes such as beeswax and carnuba. The insoluble gum base constitutes between about 5 to 95 weight percent of the gum. Preferably the insoluble gum base comprises about 10 to about 50 weight percent of the gum and more preferably about 20 to about 30 weight percent. The gum base typically also includes a filler • component. The filler component such as calcium carbonate, magnesium carbonate, talc, dicalcium phosphate and the like. The filler may constitute be¬ tween about 5 to about 60 weight percent of the gum base. Preferably, the filler comprises about 5 to 50 weight percent of the chewing gum base. Gum bases typically also contain softeners, including glycerol monostearate and glycerol tri¬ acetate. Further, gum bases may also contain optional ingredients such as antioxidants, colors, and emulsi- fiers. The present invention contemplates employing any commercially acceptable gum base. The water soluble portion of chewing gum may further comprise softeners, sweeteners, flavors and combinations thereof. Softeners are added to the chewing gum in order to optimize the chewability and mouth feel of the gum. Softeners, also known in the art as plasticizers or plasticizing agents, generally constitute between about 0.5 to about 15.0 weight percent of the chewing gum. Softeners contemplated by the present invention include glycerin, lecithin, and combinations thereof. Further, aqueous sweetener solu¬ tions such as those containing sorbitol, hydrogenated starch hydrolysates, corn syrup and combinations thereof may be used as softeners and binding agents in gum. In addition to the sweet proteins already mentioned, the present invention also contemplates the presence of other sweeteners in the chewing gum. These sweeteners include both sugar and sugarless components. Sugar sweeteners generally include saccharide contain¬ ing components commonly known in the chewing gum art which comprise but are not limited to sucrose, dextrose, maltose, dextrin, dried invert sugar, fruc¬ tose, levulose, galactose, corn syrup solids, and the like, alone or in any combination. Sugarless sweeteners include components with sweetening charac¬ teristics but are devoid of the commonly known sugars and comprise but are not limited to sugar alcohols such as sorbitol, mannitol, xylitol, hydrogenated starch hydrolysates, maltitol, and the like, alone or in any combination. Also contemplated are relatively faster releasing sweeteners such as aspartame, sucralose, acesulfame-K, cyclamates and saccharin. Those skilled in the art will recognize that any combination of sugar and/or sugarless sweeteners may be employed in the chewing gum. Further, those skilled in the art will recognize the sweetener may be present in the chewing gum in whole or in part as a water soluble bulking agent. In addition, the softener may be combined with the sweetener such as in an aqueous sweetener solution. Flavors contemplated by the present invention include any liquid flavoring which is of food accept¬ able quality. The flavor may comprise essential oils, synthetic flavors, or mixtures thereof including but not limited to oils derived from plants and fruits such as citrus oils, fruit essences, peppermint oil, spear¬ mint oil, clove oil, oil of wintergreen, anise, and the like. Artificial flavoring components are also contem¬ plated by the present invention. Those skilled in the art will recognize that natural and artificial flavors may be combined in any sensorally acceptable blend. All such flavors and blends are contemplated by the present invention. Flavors may be present in the chewing gum in an mount within the range of from about 0.1 to about 10.0 weight percent and preferably from about 0.5 to about 3.0 weight percent of the gum. The flavor may comprise the components already mentioned. Optional ingredients such as colors, emulsi- fiers and pharmaceutical agents may be added to the chewing gum. The chewing gum of the present invention is manufactured by combining chewing gum ingredients such as chewable gum base and flavor, with sweet protein and salt which are in a form such that they are substanti¬ ally physically separate in the gum. Accordingly, the present invention contemplates employing any of the commonly known chewing gum manufacturing methods which achieve a substantial physical separation of the sweet protein and salt. The chewing gum may be manufactured by adding the sweet protein and/or salt to various chewing gum ingredients in any commercially available mixer known in the art. After the ingredients have been thoroughly mixed, the gum mass is discharged from the mixer and shaped into the desired form such as by - 10 - rolling into sheets and cutting into sticks, extruding into chunks, or casting into pellets. Generally, the ingredients are mixed by first melting the gum base and adding it to the running mixer. The base may also be melted in the mixer it¬ self. Color may also be added at this time. A softener such as glycerin may then be added next along with syrup and a portion of bulking agent. Further portions of the bulking agent may then be subsequently added to the mixer. Flavor is typically added with the final portion of the bulking agent. The salt and sweet protein may be added at any time as long as either one or both of the compounds are in a form which will keep the two compounds physically separate from one another. The entire mixing procedure typically takes from five to fifteen minutes, but longer mixing times may sometimes be required. Those skilled in the art will recognize that many variations of the above described procedure may be followed. In accordance with one embodiment of the present invention, the sweet proteins contemplated may be combined in the form of an emulsion while the salt is separately added in aqueous solution. The emulsion may be formed in any way. In accordance with one em¬ bodiment, the emulsion is prepared by first dissolving the sweet protein in water to form an aqueous solution, and them emulsifying the aqueous solution with a com¬ pound possessing hydrophobic characteristics. The aqueous solution may be emulsified with the hydrophobic compound in any known manner, but it is preferred that an emulsifier be employed to accomplish this purpose. Preferably, the hydrophobic compound com¬ prises a liquid flavor oil. Such flavor oils include synthetic and natural flavoring compounds. The hydro- phobic compound may also comprise non-flavor compounds. Thus, vegetable oils and other hydrophobic non-flavor compounds are also contemplated. The aqueous sweetener solution may comprise up to 25 weight percent of the sweet protein. Con¬ centrations above 25 weight percent, however, should be avoided to prevent foaming of the solution. Prefer¬ ably, the aqueous sweet protein solution comprises about 1 weight percent of the sweet protein. In any event, the present invention contemplates aqueous solutions of various concentrations. The aqueous solution may be heated in order to enhance dissolution and/or its emulsifying action. In addition, glycerin, or a similar compound, may be added to the aqueous solution to prevent gellation. The emulsion may be prepared by mixing the aqueous solution with flavor. The emulsion may be formed by any manner known in the art, but preferably • the emulsion is formed with the aid of an emulsifier. Emulsifiers contemplated include any span, tween, or similar compound. Preferably, the emulsifier employed is matched to the hydrophobic compound by its Hydrophile-Lipophile Balance (HLB) number. The HLB of an emulsifier is an expression of its hydrophilic- lipophile balance, i.e., the balance of the size and strength of the hycrophilic and the lipophilic groups of an emulsifier. The HLB system which has been known to those skilled in the art since the later 1940' s is useful in choosing an appropriate emulsifier is lecithin, a well known, inexpensive emulsifier. The salt may be added to the chewing gum ingredients independently of the emulsion, either before or after the emulsion and in either the solid phase or dissolved in a liquid. The salt may also be modified to a form which enhances its physical separa¬ tion from the sweet protein. Accordingly the salt may be encapsulated or coated in manners known in the art. It is further contemplated that the emulsion may also comprise other ingredients nonessential to the formation of the emulsion. Such ingredients include but are not limited to coloring agents such as dyes, lakes, and natural colorants, food acids, glycerin and like components, medicants, and relatively fast releasing high potency sweeteners such as aspartame, sucralose, acesulfame-K, cyclamates, and saccharin. In accordance with another embodiment of the present invention, the chewing gum composition may com¬ prise separate portions, one portion containing the salt and the other containing the sweet protein. For example, the chewing gum may contain a core portion and a layer portion, with sweet protein and salt being present in separate portions. In addition, a high intensity sweetener may be contained in the core portion or applied to the surface of the core portion. The core portion of the chewing gum is manufactured in a conventional manner. Accordingly, the base is heated and placed in a mixer. If coloring is desired it may be added at this point followed by the sweetener, plasticizing agent and flavor. When the core portion of the chewing gum is removed from the mixer, it is rolled in conventional product forming equipment as is well known in the art. For example, a layer containing sweet protein may be deposited on the surface of a salt containing core portion by applying a rolling compound comprising the sweet protein. The rolling compound contemplated comprises sweet protein in combination with mannitol, sorbitol, sucrose, starch, calcium carbonate, talc, other orally acceptable substances or mixtures thereof. The rolling compound may comprise from about 0.25% to about 10.0% but preferably about 1% to about 3% by weight of the chewing gum composition. The rolling compound is preferably applied to the surface of the core portion by employing the well known dusting procedure immediately prior to rolling the gum in the product forming equipment in order to prevent adhesion of the gum and the rollers, particular¬ ly when the gum is warm. In accordance with another embodiment, the sweet protein may be deposited onto the surface of the core portion by using a powder spray process. In such a process the powder containing the sweet protein is suspended in a pressurized gas which is sprayed onto a surface. ' In still yet another embodiment, sweet protein may be applied to the surface of the core portion by way of a solution which is sprayed thereon. In such a process an aqueous solution containing sweet protein is formed and then sprayed as an aerosol mist. The application of sweet proteins to the surface of a chewing gum core portion is more fully described in U.S. Patent No. 4,562,076 (Arnold et al. ) . The teachings of this patent are incorporated herein by reference thereto. In accordance with a still further embodiment of the present invention, the chewing gum composition may comprise a chewable gum base shell enclosing an internal void and a liquid center fill in the void. The liquid center fill comprises sweet protein and the chewable gum base comprises salt. The shell portion of the chewing gum composi¬ tion may be manufactured by any conventional manner. Accordingly, first the base is heated and placed in a running mixer. If coloring is desired it may be added at this point followed by a bulking agent, plasticizing agent, flavor and the salt. To enhance separation either the salt or the sweet protein may be further treated'by physical separation techniques such as formation in emulsion, encapsulation, etc. When the chewing gum is removed from the mixer it is shaped and then filled with the liquid center fill using con¬ ventional product forming equipment in a known manner. The liquid center fill may comprise in addi¬ tion to sweet protein, one or more carbohydrate syrups, glycerin, thickners, flavors, acidulants, colors, sugars and sugar alcohols in conventional amounts. These ingredients may be combined in any conventional manner. Of course, the makeup may be reversed whereby the salt is present in the liquid center and the sweet protein is present in the shell. A more complete discussion of liquid center fill chewing gum compositions comprising sweet proteins and their method of manufacture is provided in U.S. Patent No. 4,642,235 (Reed et al.). This patent is incorporated herein by reference thereto. In addition to those described above, other physical separation chewing gum constructions are contemplated. Thus, the chewing gum may be flat and contain separate layers, one of which comprises the salt and the other comprises the sweet protein. Multilayered chewing gums may be produced by coex- trusion or by combining separately extruded layers. In addition, the salt and/or the sweet protein may be treated to enhance their physical separation by any technique known in the art. Such techniques include but are not limited to encapsulation, spray-drying, spray-chilling, fluid bed coating, and mixing the sweetner with aqueous gelatin followed by drying, grinding and optional granulation. It is to be understood that an equivalent range of changes and modifications to the preferred embodiments described above are also contemplated by the present invention. The following examples are not to be construed as a limitation upon the present inven¬ tion, but are included merely as an illustration of various embodiments. EXAMPLE CHEWING GUM A - SWEET PROTEIN AND SALT NOT SEPARATE A chewing gum is manufactured with a 13 minute mix schedule. At t = 0 the mixing of gum base begins and all ingredients are added by the end of the schedule. Prior to beginning the mixing, an emulsion containing salt and thaumatin is prepared. First an aqueous solution containing 10% thaumatin and 40% salt is prepared. This aqueous solution is mixed with a solution containing emulsifier such as lecithin and a hydrophobic ingredient such as flavor to form an emulsion. As the gum base mixing begins, various ingredients may be added at any time. At t = 8 minutes the emulsion containing salt and thaumatin is added to the other chewing ingredients to yield a chewing gum containing 100 ppm salt and 25 ppm thaumatin. The resulting gum may be a standard sugarless chewing gum containing commonly accepted amounts of gum base, glycerin, sorbitol, mannitol, and asparta e. CHEWING GUM B - SWEET PROTEIN AND SALT SEPARATE Identical amounts of gum base, glycerin, sorbitol, mannitol, and aspartame in the chewing gum formula may be employed in an identical 13 minute mix schedule. However, during the mix schedule a 40% aqueous salt solution is added at t = 8 minutes while an emulsion containing thaumatin but not containing salt is added at t = 10 minutes. The amount of salt solution added is sufficient to obtain 100 ppm salt in the final chewing gum product while the amount of emulsion added is sufficient to obtain 25 ppm thaumatin in the final product. The emulsion keeps the thaumatin physically separate from the salt. In a comparison of the chewing gums A and B a chewer will experience a less intense flavor and sweetness from chewing gum A. Thus the flavor and sweetness effect of the thaumatin in chewing gum will be enhanced by the physical separation of salt from the sweet protein.

Claims: I CLAIM : 1,. A chewing gum composition having enhanced flavor, said composition comprising a chewable gum base, flavor, sweet protein and between about 10 to about 1000 ppm by weight of the chewing gum of a salt selected from sodium chloride, potassium chloride or mixtures thereof wherein the sweet protein and salt are substantially physically separate. 2. The composition of claim 1 wherein the chewing gum comprises sweet protein in amounts between about 5 to about 1000 ppm by weight of the chewing gum. 3. The composition of claim 1 wherein the chewing gum comprises flavor in amounts between about 0.1 to about 10 percent by weight of the chewing gum. 4. The composition of claim 1 wherein the sweet protein comprises thaumatin or monellin. --5. The composition of claim 1 comprising two portions wherein salt is present in one portion and sweet protein is present in the other portion. 6. A method of manufacturing chewing gum com¬ prising combining a chewable gum base, flavor, sweet protein, and a salt selected from sodium chloride, potassium chloride or mixtures thereof, said salt and chewing gum being added such that they are substanti¬ ally physically separate. 7. The method of claim 6 wherein the sweet • protein comprises thaumatin. 8. The method of claim 6 wherein the sweet protein comprises monellin. 9. The method of claim 6 wherein sweet protein is combined in an amount to yield between about 5 to about 1000 ppm by weight of the chewing gum. 10. The method of claim 6 wherein salt is combined in an amount to yield between about 10 to about 1000 ppm by weight of the chewing gum. 11. The method of claim 6 wherein prior to combining, the sweet protein is first mixed with water, an emulsifier, and a hydrophobic ingredient to form an emulsion. 12. The method of claim 6 wherein a rolling compound comprising sweet protein is applied to the surface of a chewing gum base comprising salt. . 13. The method of claim 12 wherein the rolling compound comprises between about 0.25 to about 10 percent by weight of the chewing gum. 14. The method of claim 6 wherein the chewable gum base comprises a shell containing salt and having an internal void therein and the void is filled with a liquid center fill comprising sweet protein. 15. The method of claim 6 wherein a first chew¬ able gum base layer comprising salt is coextruded with a second chewable gum base layer comprising sweet protein.

Inventors: DAVE JAYANT C, PATEL MANSUKH M, DAVE, JAYANT, C., PATEL, MANSUKH, M.
Applicants: WRIGLEY W M JUN CO, WM. WRIGLEY JR. COMPANY
Application year: 1988
Main classification: A23G3
IPC codes: A23G4