AU2004201859A1 - Coated Encapsulated Active Ingredients, Chewing Gums Containing Same, and Methods of Preparing Same - Google Patents

Description

S&F Ref: 451421D2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name and Address of Applicant Actual Inventor(s): Address for Service: Invention Title: Wm. Wrigley Jr. Company, of 410 North Michigan Avenue, Chicago, Illinois, 60611, United States of America Kevin B. Broderick Spruson Ferguson St Martins Tower Level 31 Market Street Sydney NSW 2000 (CCN 3710000177) Coated Encapsulated Active Ingredients, Chewing Gums Containing Same, and Methods of Preparing Same The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5845c Coated Encapsulated Active Ingredients, Chewing Gums Containing Same, And Methods Of Preparing Same Background of the Invention The present invention relates generally to chewing gums and the manufacture of same. More specifically, the present invention relates to chewing gums having ingredients that must be encapsulated in order to prevent degradation.

It is, of course, known to prepare chewing gum including a variety of different ingredients. Some of these ingredients are used to add flavour or sweetness to the chewing gum. One of the difficulties encountered in adding certain ingredients to chewing gum is that they are vulnerable to degradation.

It is known, to add aspartame, a sugarless sweetener, to chewing gum. However, aspartame is vulnerable to degradation; upon exposure to moisture aspartame will degrade. Therefore, it has been known to encapsulate aspartame in polyvinyl acetate to prevent degradation. In a similar vein, other sensitive ingredients have been encapsulated with polyvinyl acetate to prevent degradation, for example, alitame. US 5 108 763 discloses the use of polyvinyl acetate to encapsulate sweeteners.

Unfortunately, even when encapsulated in polyvinyl acetate, aspartame is still vulnerable to degradation.

In this regard, flavour components present in the chewing gum can plasticise the polyvinyl acetate coating. This can destroy or reduce the protective effects of the polyvinyl acetate, rendering the aspartame, or other active sensitive ingredient, vulnerable to degradation. For example, it is known that polyvinyl encapsulations are not stable in certain chewing gums such as fruit flavoured gums. This is because the fruit flavour in the chewing gum plasticises the polyvinyl acetate coating of the active ingredient and compromises the integrity of the encapsulated particle.

A number of patents disclose methods of coating ingredients, such as aspartame These patents include US 4 863 745; 4 919 941; 4 931 295; 5 108 762; 5 124 160; 5 139 798; 5 154 939; 164 210; 5 165 944; 5 169 657; 5169 658; 5 112 625; 5 1 92 5 63 5 1 9 8 251; 5 364 627; and EP 484 124.

Other patents disclosing the use of coating materials include US 5 077 053; 4 384 004; 2 504 436; 3 576 663; 4 137 300; 4 194 013; 4 224,219; and 4 474 749. See also: FR 2 117 506; and JP 82- 141273 and 88-028575.

There is still, however, a need for an improved method of encapsulating sensitive active ingredients, such as aspartame, especially in fruit flavoured chewing gums.

Summary of the Invention The present invention provides encapsulated sensitive active ingredients, such as aspartame, and chewing gum including same. Pursuant to the present invention, a sensitive active ingredient, such as aspartame, that is coated with polyvinyl acetate, is coated with a second coating of zein. The zein coating protects the polyvinyl acetate encapsulation thereby protecting the sensitive active ingredient from degradation.

To this end, a chewing gum is provided including a water insoluble portion, one or more flavours, and a water soluble portion. The chewing gum also includes a sensitive active ingredient coated with a first coating of polyvinyl acetate and a second coating of zein that coats the first coating.

UbC/451421Dlspec In an embodiment, the active ingredient is chosen from the group consisting of aspartame, alitame, sucralose, and glycyrrhizin.

In an embodiment, the flavour is chosen from the group consisting of amyl acetate, lemon oil, orange oil, ethyl butyrate, ethyl propionate, ethyl acetate, ethyl alcohol, ethyl caproate, and aldehyde flavours.

In an embodiment, the second coating is applied at a weight ratio of approximately 1:10 to about 1:1 as compared to a total cumulative weight of the first coating and sensitive active ingredient.

In an embodiment, the second coating is applied by wet granulation.

In another embodiment, an encapsulated sensitive active ingredient is provided comprising: a sensitive active ingredient; a first coating of polyvinyl acetate that coats at least a substantial portion of an outer surface of the sensitive active ingredient; and a second coating of zein that coats at least a substantial portion of an outer surface of the first coating.

In still another embodiment, a method for preparing chewing gum is provided comprising the steps of: coating a sensitive active ingredient with polyvinyl acetate to create an encapsulated product; and coating the encapsulated product with a solution chosen from the group consisting of zein, gelatine, and water soluble proteins.

In an embodiment, the sensitive active ingredient is coated with polyvinyl acetate through wet granulation, wax granulation, spray drying, spray chilling, fluid bed coating, coacervation, extrusion, or fibre spinning.

An advantage of the present invention is to provide an improved chewing gum composition.

Still further, an advantage of the present invention is to provide an improved method of encapsulating sensitive active ingredients.

Moreover, an advantage of the present invention is to provide sensitive active ingredients that are encapsulated so as to prevent degradation of the ingredients.

Furthermore, an advantage of the present invention is to provide an improved method for protecting sensitive active ingredients in chewing gum compositions especially those including fruit flavour.

Another advantage of the present invention is to provide an improved method for manufacturing chewing gum.

Still further, an advantage of the present invention is to provide an improved method for protecting sweeteners from degradation in chewing gum.

Further, an advantage of the present invention is to provide an improved method for encapsulating moisture sensitive ingredients.

Additional features and advantages of the present invention are described in, and will be apparent from, the detailed description of the presently preferred embodiments and from the Figure.

Brief Description of the Figure The Figure illustrates graphically the results of the experiments set forth as Examples 1-3 below.

LibC/451421Dlspeci Detailed Description Of The Presently Preferred Embodiments The present invention provides an improved method for encapsulating sensitive active ingredients, such as aspartame and alitame. Pursuant to the present invention, the sensitive active ingredients are encapsulated by a first coating of polyvinyl acetate. The polyvinyl acetate coating is s then encapsulated by, preferably, a coating of zein. By so encapsulating the polyvinyl acetate coating, the coating of polyvinyl acetate is protected from degradation, and specifically from being plasticised by flavours such as fruit. This therefore protects the polyvinyl acetate encapsulation of the sensitive active ingredient. It should also be noted that it may be desirable to coat an ingredient to provide longer flavour or sweetness and thereby control the release of the ingredient.

There are a number of methods of encapsulating aspartame, or like sensitive active ingredients, with polyvinyl acetate. Any such method can be used pursuant to the present invention including wet granulation, wax granulation, spray drying, spray chilling, fluid bed coating, coacervation, extrusion or fibre spinning. Preferably, the ratio of sensitive active ingredient, eg., aspartame, to polyvinyl acetate when so coated is preferably from approximately 1:9 to about 1:4. As used herein, "sensitive active ingredient" refers to any ingredient that can be used in a confectionery or food product that upon exposure to the ambient environment, or other ingredients in the product, will degrade and not fully provide its desired properties or characteristics. Aspartame and alitame are examples of sensitive active ingredients. The present invention can be used to protect such sensitive active ingredients.

To this end, in an embodiment, the present invention provides a coating of zein that is used to coat a layer of polyvinyl acetate that surrounds the sensitive active ingredient, such as aspartame.

Although preferably zein is used to encapsulate the polyvinyl acetate coating, if desired other compositions can be used instead of zein such as gelatine and water soluble proteins such as casein, soy and glutan.

Pursuant to the present invention, in an embodiment, once the sensitive active ingredient, eg., aspartame, is encapsulated by the polyvinyl acetate, it is then coated with an aqueous zein solution.

The zein solution is made by dispersing approximately 5 to about 20% by weight powdered zein in approximately 80 to about 95% by weight water. Preferably, the resultant product has a pH of approximately 8 to about 10.5.

During the process, in order to dissolve the zein, the pH of the dispersion is increased to approximately 11.6 to about 11.9. The zein solution is then in a condition that it can be applied to the polyvinyl acetate encapsulated aspartame by a number of methods including wet granulation.

The zein solution is applied so that, preferably, the ratio of zein to the polyvinyl acetate encapsulated sensitive active ingredient is from about 1:10 to about 1:1.

In creating a chewing gum product, the zein overcoated polyvinyl acetate coated sensitive active ingredients can be added so that the resultant chewing gum product comprises approximately 0.01 to about 3wt% of the overcoated ingredients. Most preferably, the overcoated ingredients are added at a ratio of approximately 0.1 to about 1.5% and in a preferred embodiment, approximately 0.3 to about 0.8%.

UbC/451421D1spec There are a variety of different gums that the zein overcoated polyvinyl acetate coated sensitive active ingredients can be used in. In a preferred embodiment, the overcoated ingredients will be used in fruit flavoured chewing gum.

There are a variety-of fruit flavours that are used in chewing gums, such as, amyl acetate, lemon oil, orange oil, ethyl butyrate, ethyl propionate, ethyl acetate, ethyl alcohol and ethyl caproate.

The zein overcoated ingredient could also be used in chewing gums containing aldehyde flavours such as cinnamic aldehyde to protect the aspartame from being degraded by the aldehyde. Additional (non-fruit) flavours may optionally be included such as peppermint oil, spearmint oil, other mint oils, clove oil, .oil of wintergreen, and anise. The flavour is generally present in the gum at approximately 0.3 to about 10wt% of the gum.

The chewing gum that utilises the present invention may be any of a variety of different chewing gums, including low or high moisture, sugar or sugarless, wax-containing or wax-free, low calorie and/or a chewing gum that includes dental health agents.

Chewing gum generally consists of a water insoluble gum base, a water soluble portion, and flavours. The water soluble portion dissipates with a portion of the flavour over a period of time during chewing. The gum base portion is retained in the mouth throughout the chew.

The insoluble gum base generally comprises elastomers, resins, fats and oils, softeners, and inorganic fillers. The gum base may or may not include wax. The insoluble gum base can constitute approximately 5 to about 95wt%, of the chewing gum, more commonly, the gum base comprises 10 to about 50wt% of the gum, and in some preferred embodiments, 20 to about 35wt%, of the chewing gum. In an embodiment, the chewing gum base of the present invention contains about 20 to about weight percent synthetic elastomer, 0 to about 30 weight percent natural elastomer, about 5 to about elastomer plasticiser, about 4 to about 35wt% filler, about 5 to about 35wt% softener, and optional minor amounts (about 1% or less) of miscellaneous ingredients such as colorants, antioxidants, etc.

Synthetic elastomers may include, but are not limited to, polyisobutylene with a GPC weight average molecular weight of about 10 000 to about 95 000, isobutylene-isoprene copolymer (butyl elastomer), styrene-butadiene copolymers having styrene-butadiene ratios of about 1:3 to about 3:1, polyvinyl acetate having a GPC weight average molecular weight of about 2000 to about 90 000, polyisoprene, polyethylene, vinyl acetate-vinyl laurate copolymer having vinyl laurate content of about to about 50wt% of the copolymer, and combinations thereof.

Preferred ranges are, for polyisobutylene, 50 000 to 80 000 GPC weight average molecular weight, for styrene-butadiene, 1:1 to 1:3 bound styrene-butadiene, for polyvinyl acetate, 10 000 to 000 GPC weight average molecular weight with the higher molecular weight polyvinyl acetates typically used in bubble gum base, and for vinyl acetate-vinyl laurate, vinyl laurate content of 10-45%.

Natural elastomers may include natural rubber such as smoked or liquid latex and guayule as well as natural gums such as jelutong, lechi caspi, perillo, sorva, massaranduba balata, massaranduba chocolate, nispero, rosindinha, chicle, gutta hang kang, and combinations thereof. The preferred synthetic elastomer and natural elastomer concentrations vary depending on whether the chewing gum in which the base is used is adhesive or conventional, bubble gum or regular gum, as LbC/451421Dlspeci discussed below. Preferred natural elastomers include jelutong, chicle, sorva and massaranduba balata.

Elastomer plasticisers may include, but are not limited to, natural rosin esters such as glycerol esters of partially hydrogenated rosin, glycerol esters polymerised-rosin, glycerol esters of partially dimerised rosin, glycerol esters of rosin, pentaerythritol esters of partially hydrogenated rosin, methyl and partially hydrogenated methyl esters of rosin, pentaerythritol esters of rosin; synthetics such as terpene resins derived from alpha-pinene, beta-pinene, and/or d-limonene; and any suitable combinations of the foregoing. The preferred elastomer plasticisers will also vary depending on the specific application, and on the type of elastomer which is used.

Fillers/texturisers may include magnesium and calcium carbonate, ground limestone, silicate types such as magnesium and aluminium silicate, clay, alumina, talc, titanium oxide, mono-, di- and tri-calcium phosphate, cellulose polymers, such as wood, and combinations thereof.

Softeners/emulsifiers may include tallow, hydrogenated tallow, hydrogenated and partially hydrogenated vegetable oils, cocoa butter, glycerol monostearate, glycerol triacetate, lecithin, mono-, di- and triglycerides, acetylated monoglycerides, fatty acids (eg. stearic, palmitic, oleic and linoleic acids), and combinations thereof.

Colorants and whiteners may include FD&C-type dyes and lakes, fruit and vegetable extracts, titanium dioxide, and combinations thereof.

The base may or may not include wax. An example of a wax-free gum base is disclosed in US 5 286 500, the disclosure of which is incorporated herein by reference.

In addition to a water insoluble gum base portion, a typical chewing gum composition includes a water soluble bulk portion and one or more flavouring agents.

The water soluble portion can include bulk sweeteners, high intensity sweeteners, flavouring agents, softeners, emulsifiers, colours, acidulants, fillers, antioxidants, and other components that provide desired attributes.

Softeners are added to the chewing gum in order to optimise the chewability and mouth feel of the gum. The softeners, which are also known as plasticisers and plasticising agents, generally constitute between approximately 0.5 to about 15wt% of the chewing gum. The softeners may include glycerin, lecithin, and combinations thereof. Aqueous sweetener solutions such as those containing sorbitol, hydrogenated starch hydrolysates, corn syrup and combinations thereof, may also be used as softeners and binding agents in chewing gum.

Bulk sweeteners include both sugar and sugarless components. Bulk sweeteners typically constitute 5 to about 95wt% of the chewing gum, more typically, 20 to 80wt%, and more commonly, to 60wt% of the gum.

Sugar sweeteners generally include saccharide-containing components commonly known in the chewing gum art, including, but not limited to, sucrose, dextrose, maltose, dextrin, dried invert sugar, fructose, levulose, galactose, corn syrup solids, and the like, alone or in combination.

Sugarless sweeteners include, but are not limited to, sugar alcohols such as sorbitol, mannitol, xylitol, hydrogenated starch hydrolysates, maltitol, and the like, alone or in combination.

UbC/451421Dspeci High intensity artificial sweeteners can also be used, alone or in combination with the above.

Preferred sweeteners include, but are not limited to sucralose, aspartame, salts of acesulfame, alitame, saccharin and its salts, cyclamic acid and its salts, glycyrrhizin, dihydrochalcones, thaumatin, monellin, and the like, alone or in combination.

Usage level of the artificial sweetener will vary greatly and will depend on such factors as potency of the sweetener, rate of release, desired sweetness of the product, level and type of flavour used and cost considerations. Thus, the active level of artificial sweetener may vary from 0.02 to about When carriers used for encapsulation are included, the usage level of the encapsulated sweetener will be proportionately higher.

Combinations of sugar and/or sugarless sweeteners may be used in chewing gum. Additionally, the softener may also provide additional sweetness such as with aqueous sugar or alditol solutions.

Flavour should generally be present in the chewing gum in an amount within the range of about 0.1-15wt% of the chewing gum, preferably between about 0.2-5wt% of the chewing gum, mostly preferably between about 0.5-3wt% of the chewing gum.

is Flavouring agents may include essential oils, synthetic flavours or mixtures thereof including, but not limited to, oils derived from plants and fruits such as citrus oils, fruit essences, peppermint oil, spearmint oil, other mint oils, clove oil, oil of wintergreen, anise and the like. Artificial flavouring agents and components may also be used in the flavour ingredient of the invention. Natural and artificial flavouring agents may be combined in any sensorially acceptable fashion.

Optional ingredients such as colours, emulsifiers, pharmaceutical agents and additional flavouring agents may also be included in chewing gum.

Chewing gum is generally manufactured by sequentially adding the various chewing gum ingredients to 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 rolling into sheets, scoring and cutting into pieces.

Generally, the ingredients are mixed by first melting the gum base and adding it to the running mixer.

The gum base may alternatively be melted in the mixer. Colour and emulsifiers can be added at this time.

A softener such as glycerin can be added next along with syrup and part of the bulk portion.

Further, parts of the bulk portion may then be added to the mixer. Flavouring agents are typically added with the final part of the bulk portion. The entire mixing process typically takes from five to fifteen minutes, although longer mixing times are sometimes required. Those skilled in the art will recognise that variations of this mixing procedure, or other mixing procedures, may be followed.

By way of example, and not limitation, examples of the present invention will now be given.

Example 1 Aspartame was obtained in the form of a fine, white powder and placed into fruit flavoured chewing gum at O.10wt% of the gum. The gum formula is set forth below in Table 1 as Example 1.

Example 2 A mixture of aspartame and polyvinyl acetate (PVAc) was melt spun into fibres in an extruder.

After the fibres were formed, they were stretched by applying a stretching force such as a draw. The ibC/451421D1speci fibres were then cut and placed into fruit flavoured chewing gum at 0.5wt% of the gum. The gum formula is set forth below in Table 1 as Example 2.

Example 3 The polyvinyl acetate encapsulated aspartame of Example 2 was used to make a zein overcoated ingredient. A zein solution comprising 15% zein and 85% water was granulated with the polyvinyl acetate/aspartame ingredient by adding the solution slowly so as to slightly dampen the polyvinyl acetate/aspartame ingredient with the zein solution, then dried and ground. The zein overcoated ingredient was added into fruit flavoured chewing gum at 0.5% by weight of the gum. The gum formula as set forth below in Table 1 as Example 3. The following table shows the gum formulas for each example. The ingredients are given in weight percentage.

Table 1 Ex.1 Ex.2 Ex.3 Sugar 57.43% 57.03% 57.03% Gum Base 19.30 19.30 19.30 Dextrose Monohydrate 7.28 7.28 7.28 Corn Syrup 13.91 13.91 13.91 Glycerin 1.15 1.15 1.15 Fruit Flavour 0.70 0.70 0.70 Lecithin 0.13 0.13 0.13 Free Aspartame 0.10 PVAc Encapsulate Aspartame 0.50 Zein Overcoated Aspartame 0.50 Accelerated aging tests were conducted with the gum samples. The gum samples were placed in 30°C for 60 days. The gum samples were analysed by HPLC to determine the stability of the aspartame over the 60 days. The Figure illustrates graphically the percent loss of aspartame over time. As illustrated aspartame had the greatest stability when it was encapsulated with polyvinyl acetate and overcoated with zein (Example 3).

It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without diminishing its attendant advantages. It is therefore intended that such changes and modifications be covered by the appended claims.

LibC/451421D1spec

Claims (21)

1. A chewing gum including: a water insoluble portion; one or more flavours; a water soluble portion; and a sensitive active ingredient coated with a first coating of polyvinyl acetate that substantially surrounds the sensitive active ingredient and a second coating of zein that substantially coats the first coating.

2. The chewing gum of claim 1 wherein the active ingredient is chosen from the group consisting of aspartame, alitame, sucralose, and glycyrrhizin.

3. The chewing gum of claim 1 or claim 2 wherein the flavour is chosen from the group consisting of amyl acetate, lemon oil, orange oil, ethyl butyrate, ethyl propionate, ethyl acetate, ethyl alcohol, ethyl caproate, and aldehyde flavours.

4. The chewing gum of any one of claims 1 to 3 wherein the second coating is applied at a weight ratio of about 1:10 to about 1:1 as compared to a total cumulative weight of the first coating and sensitive active ingredient.

The chewing gum of any one of claims 1 to 4 wherein the second coating is applied by wet granulation.

6. A chewing gum, substantially as hereinbefore described with reference to any one of the examples.

7. An encapsulated sensitive active ingredient comprising: a sensitive active ingredient; a first coating of polyvinyl acetate that coats at least a substantial portion of an outer surface of the sensitive active ingredient; and a second coating of zein that coats at least a substantial portion of an outer surface of the first coating.

8. The encapsulated sensitive active ingredient of claim 7 wherein the active ingredient is chosen from the group consisting of aspartame, alitame, sucralose, and glycyrrhizin.

9. The encapsulated sensitive active ingredient of claim 7 or claim 8 wherein the second coating is applied at a weight ratio of about 1:10 to about 1:1 as compared to a total cumulative weight of the first coating and the sensitive active ingredient.

The encapsulated sensitive active ingredient of any one of claims 7 to 9 wherein the second coating is applied by wet granulation.

11. The encapsulated sensitive active ingredient of any one of claims 7 to 10 wherein the encapsulated sensitive ingredient is used in a confectionery product.

12. The encapsulated sensitive active ingredient of any one of claims 7 to 11 wherein the encapsulated sensitive ingredient is used in a chewing gum.

13. The encapsulated sensitive active ingredient, substantially as hereinbefore described with reference to any one of the examples.

14. A method for preparing chewing gum comprising the steps of: coating a sensitive active ingredient with polyvinyl acetate to create an encapsulated product; and coating the encapsulated product with a solution chosen from the group consisting of zein, gelatine and water soluble proteins. The method of claim 14 wherein the water soluble proteins are chosen from the group consisting of casein, soy, and gelatine.

LibC451421O1speci

16. The method of claim 14 or claim 15 wherein the sensitive active ingredient is coated with polyvinyl acetate through wet granulation, wax granulation, spray drying, spray chilling, fluid bed coating, coacervation, extrusion, or fibre spinning.

17. The method of any one of claims 14 to 16 wherein the solution is coated on the encapsulated product through wet granulation.

18. The method of any one of claims 14 to 17 wherein the solution includes zein.

19. The method of any one of claims 14 to 18 wherein the sensitive active ingredient is aspartame.

A method for preparing chewing gum, substantially as hereinbefore described with reference to any one of the examples.

21. Chewing gum prepared by the method of any one of claims 14 to Dated 30 April 2004 WM. WRIGLEY JR. COMPANY Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON LibC/451421Dl1sped