WO1993022939A1

WO1993022939A1 - Improved high intensity sweetener ingredient

Info

Publication number: WO1993022939A1
Application number: PCT/US1993/004401
Authority: WO
Inventors: Marc A. Meyers; Joo Hae Song; Adebisi A. Campbell; Gordon N. Mcgrew
Original assignee: Wm. Wrigley, Jr. Company
Priority date: 1992-05-11
Filing date: 1993-05-10
Publication date: 1993-11-25
Also published as: AU4241893A

Abstract

An improved high intensity sweetener ingredient is provided which utilizes aspartame having a specific dual morphology as the active ingredient. The aspartame having dual morphology is combined with an encapsulating and/or agglomerating agent to form a high intensity sweetener ingredient having slower release characteristics and longer shelf life than conventional coated aspartame. A method for preparing the improved high intensity sweetener ingredient is also provided. An improved chewing gum composition, and a method for preparing the improved chewing gum composition, are also provided.

Description

IMPROVED HIGH INTENSITY SWEETENER INGREDIENT

FIELD OF THE INVENTION

This invention relates to encapsulated aspartame having improved properties when used in chewing gum. More specifically, the invention relates to encapsulated aspartame having improved sweetener release and stability characteristics.

BACKGROUND OF THE INVENTION

Various methods are known for coating or encapsulatihg sweeteners and flavors in order to delay or otherwise control their release characteristics in chewing gum. Most notably, attempts have been made to delay the release of sweeteners, especially high intensity sweeteners, in order to lengthen the satis¬ factory chewing time of the gum. Delaying the release of sweetness and flavors can also avoid an undesirable overpowering burst of sweetness or flavor during the initial chewing period. Furthermore, efforts have been directed at coating or encapsulating high intensity sweeteners in order to protect them from degradation, thereby increasing their shelf stability within the chewing gum, over a period of time.

For example, U.S. Patent 4,597,970 to Shar a et al., discloses a process for producing an agglomer¬ ated sweetener wherein the sweetener is dispersed in a hydrophobic matrix of lecithin, glyceride, and fatty acid or wax. The method disclosed uses spray congeal¬ ing to form the sweetener-containing matrix into droplets, followed by fluid bed-coating of the agglomerated particles.

U.S. Patent 4,230,687 to Sair et al., teaches a process for encasing an active ingredient to achieve gradual release. The active ingredient is added to an encapsulating material in the form of a viscous paste. The components are then blended, dried and ground.

U.S. Patent 4,863,745 to Zibell discloses a method for producing a chewing gum with a delayed release high intensity sweetener wherein the high intensity sweetener has been twice coated, with the second coating being a zein composition.

U.S. patents 4,515,769 and 4,386,106 to Merritt et al. disclose a process for achieving delayed release wherein the active ingredient is prepared in an emulsion with a hydrophobic matrix. The emulsion is dried and ground and the particles are then coated with a water impermeable substance.

U.S. Patent 4,139,639 to Bahoshy et al. teaches a process for "fixing" aspartame by co-drying a solution containing aspartame and an encapsulating agent, such as gum arabic, to thereby surround and protect the aspartame during storage in the gum.

U.S. Patent 4,384,004 to Cea et al. teaches a method of encapsulating aspartame with various solutions of encapsulating agents using various encapsulation techniques such as spray drying to increase the shelf-stability of the aspartame.

U.S. Patent 4,634,593 to Stroz et al. teaches a method of producing controlled release sweeteners wherein an insoluble fat material is mix mulled with the sweetener.

Aspartame, as it has typically been used, is known to present problems relating to stabilization and encapsulation due to its morphological configuration. Typical aspartame is known to consist mainly of needle shaped crystals characteristic of cylindrical crystal packing. The bulk of the weight of typical aspartame is characterized by needles having diameters ranging from about 5 to about 30 microns and lengths ranging from about 20 to over 200 microns. The remainder of the typical aspartame, constituting a majority of the individual crystals by number but a minor percentage of the weight, is characterized by micro-needles having diameters ranging from submicron to about 3 microns and lengths ranging up to about 15 microns.

As a result, it has been very difficult to coat or encapsulate aspartame using many of the techniques that are employed with other high potency sweeteners and active ingredients. For instance, coatings must be able to wet and adhere to the needle¬ like surfaces of the aspartame. The morphological characteristics of typical aspartame, and the problems encountered in coating and encapsulating typical aspartame, are discussed further in the following United States patents:

4,981,698 4,822,621

4,933,190 4,816,265

4,931,293 4,804,548

4,839,184 4,752,485

4,828,857 4,722,845

4,822,622 4,597,970

In addition to varying the coating and encapsulation techniques, efforts to provide improved coated or encapsulated aspartame have also focused on altering the physical structure of the aspartame through grinding. U.S. Patent 4,594,252 discloses the coating of cereal using a finely ground dipeptide sweetener such as aspartame. The aspartame is in the form of discrete granules having a particle size range of about 25 to about 500 microns in diameter, with granules below 150 microns in diameter being preferred.

U.S. Patent 4,517,214 to Shoaf et al., dis¬ closes the use in comestibles of crystals of aspartame which have been subdivided by hydro illing them to a uniform particle size distribution. The aspartame is passed through a mill having a space less than 125 microns between the working mill faces.

U.S. Patent 3,943,258 to Bahoshy et al., discloses the co-grinding of aspartame with organic or inorganic acids, in order to heighten the sweetness perception in chewing gum by increasing the solubility of the aspartame. U.S. Patent 3,868,472 to Berg et al. i also discloses the co-grinding of aspartame with an acid to increase the solubility of the aspartame.

PCT Publication No. WO 89/00819 discloses the use of uniform spherical aspartame granules to permit uniform sustained release of the aspartame and uniform encapsulation. Canadian Application No. 2,029,297 discloses the use, in chewing gum, of spheronized aspartame having a narrow particle size range which does not vary by more than about 20 mesh between the smallest and largest particles. PCT Publication No. WO 90/14015 discloses the stabilization of aspartame used in chewing gum, by agglomerating the aspartame with cellulose, and drying and grinding the agglomeration product to produce particles essentially having a maximum particle size of 0.017 inches.

SUMMARY OF THE INVENTION

It has been discovered that higher quality encapsulations and granulations can be made using aspartame which has a specific dual morphology. The aspartame which is effective for this purpose includes a first aspartame morphological component A, a second aspartame morphological component B, and a third aspartame morphological component C.

Component A is aspartame whose morphology is characterized by micro-needles having diameters ranging from submicron to about 3 microns, and lengths ranging from about 2 microns to about 15 microns. Component A constitutes about 65 to about 95 weight percent of the total aspartame, preferably about 75 to about 85 weight percent of the total aspartame, most preferably about 80 weight percent of the total aspartame.

Component B is aspartame whose morphology is characterized by approximately spherical or spherically packed crystals having diameters ranging from about 40 to about 200 microns. Component B constitutes about 5 to about 35 weight percent of the total aspartame, preferably about 15 to about 25 weight percent of the total aspartame, most preferably about 20 weight percent of the total aspartame.

Component C reflects the amount of aspartame that can be used with the invention whose crystal morphology is not restricted. For example, component C may include the aspartame needles of the prior art having diameters ranging from about 5 to about 30 microns and lengths ranging from about 20 to about 200 or more microns. Component C constitutes zero to about 10 weight percent of the total aspartame, preferably less than about 5 weight percent of the total aspartame, most preferably about zero weight percent of the total aspartame.

The dual morphology aspartame described above may be coated using any of the encapsulation or agglomeration techniques known in the art, including spray drying, fluidized bed encapsulation, extrusion, fiber spinning, spray chilling and coacervation, but is preferably coated using the granulation technique described below in the DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS. The coated dual morphology aspartame of the invention, when used in chewing gum, has been found to exhibit improved (i.e. slower) release during chewing, and longer shelf stability, compared with the coated aspartame ingredients of the prior art.

With the foregoing in mind, it is a feature and advantage of the invention to provide an improved coated aspartame sweetener ingredient, using dual morphology aspartame, which exhibits longer shelf stability and improved release characteristics when used in chewing gum.

It is also a feature and advantage of the invention to provide a method for preparing the improved coated aspartame sweetener ingredient of the invention.

Another feature and advantage of the invention is to provide an improved chewing gum, sweetened with coated aspartame, which has improved shelf stability and longer lasting sweetness during chewing.

Another feature and advantage of the invention is to provide a method of making the improved chewing gum of the invention.

The foregoing and other features and advant¬ ages will become further apparent from the following DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS, read in conjunction with the accompanying Figures and Examples. The Detailed Description, Figures and Examples are to be construed as illustrative rather than limitative, with the scope of the invention being defined by the appended claims and equivalents thereof.

BRIEF DESCRIPTION OF THE FIGURES

FIGURE 1(a) is a photomicrograph showing the crystalline structure of aspartame of the prior art. FIGURE 1(b) is a photomicrograph showing the crystalline structure of the dual morphology aspartame as used with the invention.

FIGURE 2(a) is a photomicrograph showing agglomerated aspartame of the prior art, prepared according to Example 1.

FIGURE 2(b) is a photomicrograph showing agglomerated dual morphology aspartame, prepared according to Example 2.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

In accordance with the invention, a quantity of dual morphology aspartame, as described above, is mixed with a coating (i.e. agglomerating or encapsulating) agent, such as a modified cellulose, and a limited quantity of a solvent, such as water. The quantity of solvent is limited so as to produce a mixture which is only moist or damp. The damp mixture is characterized as being dust-free, non-flowing and crumbly. The damp mixture is then dried.

The dried mixture is treated, such as by grinding and/or screening, to produce the desired particle size range in the coated dual morphology aspartame particles. The coated ingredient particles comprise collections or clusters of aspartame particles which have been bound together with the coating agent.

While the aspartame may be encapsulated or agglomerated, the presently preferred coating agent is an agglomerating agent, hydroxypropyl methylcellulose (HPMC) . The dual morphology aspartame is dry blended with powdered HPMC in amounts such that the dry blend most preferably comprises about 15 weight percent HPMC and about 85 weight percent dual morphology aspartame. The blending is preferably accomplished in a planetary or other type of mixer which imparts compressive forces between the components. Water is next added to the dry blend in small increments until the resulting damp mixture includes most preferably about 36 weight percent water. The damp mixture is spread out on trays and dried at about 170^βF for 12 to 14 hours. After drying, the agglomeration mixture preferably includes between 2 and 3 percent water. The dried mixture is then ground using a high speed grinder with a 0.05 inch screen.

The present invention also contemplates the use of one or more active ingredients in addition to the dual morphology aspartame. For example, a flavor¬ ing agent may be blended together with the dual morphology aspartame and agglomerating agent so as to produce agglomerated particles that will cause a controlled release of both aspartame and flavoring agent.

The HPMC which is used as the most preferred agglomerating agent can be obtained from the Dow Chemical Company under the trade name Methocel E4M. However, other encapsulating and/or agglomerating agents can alternatively be used, including, for example, other modified cellulose compounds; gums, such as gum arabic; shellac; alcohol soluble proteins, such as zein; starches; maltodextrins; lactose; carbohydrate syrups; polymers, such as polyolefins, polyesters, and polyvinyl acetate. Where necessary, plasticizers, conditioners, lubricants, fillers and other materials may also be used in the coating to facilitate processing or improve qualities of the finished ingredient.

The present invention also contemplates the simultaneous use of more than one encapsulating and/or agglomerating agent. For example, two or more different types of HPMC can be blended so as to modify the properties of the agent as a whole. Also, it may be desirable to use two or more coating agents which have different solubility characteristics, in order to produce a stepped release of the dual morphology aspartame.

The present invention also contemplates the use of more than one coating step whereby more than one layer of coating agent can be applied to the clusters of agglomerated ingredient particles. Depending on the result desired, it may be desirable to use either the same or different coating agents in each of the layers.

The relative proportion of coating agent to dual morphology aspartame depends on the release properties which are being sought and the type of encapsulating and/or agglomerating agent selected. Generally, the use of more coating agent will result in a slower release of the aspartame (and other active ingredient, if used) when the gum is chewed. The amount of coating agent should be kept below levels which would adversely affect the flavor or texture of the chewing gum. Generally, the coating agent will comprise between about 1 and about 65 weight percent of the combined weight of the active ingredient and coating agent, preferably about 5 to about 50 weight percent of the combined weight of active ingredient and coating agent, and more preferably about 10 to about 30 weight percent.

As stated above, the dual morphology aspartame and other active ingredient, if included, are preferably dry blended with the HPMC agglomerating agent before any solvent is added. However, alternative embodiments contemplate the addition of solvent to the active ingredient and/or the coating agent, before the active ingredient and coating agent are combined. For example, when shellac is used as an agglomerating agent, the shellac is preferably used with an ethanol solvent already present. A carbo¬ hydrate syrup can be used both as an agglomerating agent and a solvent. The selection of solvent will depend on the selection of coating agent. When using HPMC as the agglomerating agent, the preferred solvent is water. When using shellac or zein as the agglomerating agent, the preferred solvent is ethanol. High pH aqueous solutions of zein or aqueous suspensions or emulsions of shellac may also be employed. The total amount of solvent added will also depend on the selection of coating agent. The amount of solvent is intentionally limited so as to produce a damp, dust-free, non- flowable, non-extrudable crumbly mixture. By the word "crumbly" it is meant that the damp mix easily separates from itself.

By way of comparison, the damp mix should have the consistency and texture of wet sand. By way of contrast, the damp mix should not have so much solvent that it becomes like dough, paste, clay or soup. If the mix becomes like dough or paste, the mix is more difficult to blend, handle, dry and grind to the desired particle size. Preferably, the solvent is added in small increments and thoroughly blended at each increment, in order to facilitate monitoring of the consistency of the mix and to prevent the formation of clay-like pools or lumps within the mixture.

One method of determining when there is sufficient solvent in the damp mix is to monitor the power demand for the mixer. Typically, the power demand increases dramatically when the mix begins to transform from the desired damp mix consistency to a dough-like consistency. This is believed to be due to the fact that in the desired damp mix stage, the mix is crumbly and easily separable, whereas when the mix becomes like dough or clay, the components become much more cohesive. It is also possible to determine the optimum amount of solvent by visually monitoring the condition of the damp mix. In the most preferred embodiment, wherein HPMC is used to agglomerate dual morphology aspartame, the water is added so as to comprise about 20 to about 55 weight percent of the damp mix, preferably about 30 to about 40 weight percent, and most preferably about 36 weight percent. When zein is used to agglomerate the dual morphology aspartame, ethanol is preferably added in an amount of about 25 to about 50 weight percent of the damp mix. When pre-solvated shellac is used, it may be added to the aspartame in the manner disclosed above for the solvent, in order to agglomerate dual morphology aspartame. Additional ethanol may be added in an amount of about 7 to about 15 weight percent of the damp mix.

After the last of the solvent is added, the combination is continually mixed until a homogeneous mass is achieved. The type of mixing is believed to be important. In particular, it is believed that compressive mixing is important in order to push the solvated agglomerating agent and aspartame together into clusters. Accordingly, the preferred type of mixer is a planetary mixer or other mixer that gives similarly compressive type mixing.

After the final mixing, the damp mix is dried so as to remove most of the solvent. Drying is prefer¬ ably accomplished by spreading the damp mix on drying trays. Preferably, the drying trays are lined with paper to facilitate removal of the dried product. Preferably, the damp mix is spread on the trays of a depth of about 2 cm.

The preferred time and temperature of drying depend largely on the type and amount of solvent used, as well as the thermal or moisture stability of the components. In the most preferred embodiment, the dual morphology aspartame agglomerated with HPMC is dried at 170°F for 12 to 14 hours, to give a product having a moisture content of about 2 to about 3 weight percent. After drying, the mix is in the form of hard, dry lumps of various shapes and sizes.

At this point, the dry mix can be ground or rolled to produce particles having the desired size range. The desired particle size range may vary depending on the type and amount of agglomerating agent used, the desired release characteristics, and other factors. Presently, a grinder having a screen with 0.05 inch holes is used to produce the agglomerated dual morphology aspartame particles of the most preferred embodiment.

A suitable dual morphology aspartame having the properties described above in the Summary Of The Invention, can be purchased from the Holland Sweetener Company under the designation Sanecta (Fine Powder Grade) . A photomicrograph for the Sanecta aspartame, illustrating the small crystalline micro-needles and the larger spherical or spherically packed crystals, is shown in FIG. 1(b). By way of comparison, a photomicrograph of conventional Nutra*Sweet aspartame, which is composed mainly of large cylindrically packed needle-shaped crystals, is shown in FIG. 1(a).

Alternatively, dual morphology aspartame suitable for use with the invention may be prepared from coarser forms of aspartame using high speed grinding techniques which are capable of producing the degree of fineness described above as micro-needles. Examples of suitable grinding techniques include pin milling and jet milling.

Several methods of including the larger spherical particles or spherically packed crystals in the dual morphology aspartame are contemplated. First, an air classification system can be used in conjunction with one of the above described milling techniques. An air classification system can be used to obtain non- uniform milling which produces a suitable dual morphology aspartame. Second, a milling process can be carried out incompletely with respect to some of the aspartame being milled. Then, partially milled aspartame can be added to completely milled aspartame.

Third, suitable larger particles can be produced using a different, coarser milling process. These larger particles can then be dry blended with the micro-needles produced by one of the fine milling processes.

An aspartame product can be tested for suitability for the present invention using an Alpine sieving apparatus. This device uses vacuum to pull the aspartame through a standard sieve. For the present invention, a U.S. Standard 325 mesh sieve is used.

A weighed quantity of aspartame (about 10 grams) is placed on the sieve and the vacuum apparatus is started. After about two minutes, the vacuum is stopped and aspartame sticking to the lid or sides of the sieve is brushed into the sieve. The vacuum/brushing cycle is then repeated.

After the final vacuum cycle, the aspartame retained on the 325 mesh sieve is carefully removed and weighed. Aspartame suitable for use with the invention will include about 5 to about 35 weight percent of these larger particles. The finer aspartame passing through the 325 mesh sieve constitutes the remainder. This finer aspartame, when examined using a scanning electron microscope (SEM) , will be seen to be composed primarily of micro-needles of the dimensions previously described.

The dual morphology aspartame used with the present invention will typically have a lower bulk density than the coarser aspartame used in prior art chewing gums. The packed bulk density for the dual morphology aspartame will typically be about 0.3 g/cm , compared with values closer to 0.4 g/cm for prior art aspartame. When the dual morphology aspartame is agglomerated and/or encapsulated using any of the various known techniques, including the preferred agglomeration techniques described herein, the product is more thoroughly and uniformly coated than when prior art aspartame is used. Furthermore, when the coated dual morphology aspartame is used in chewing gum, the aspartame will exhibit improved (i.e. slower) sweetener release during chewing, and longer shelf stability during storage of the chewing gum.

A chewing gum composition generally includes a water soluble bulk portion, a water insoluble chewing gum base portion and one or more flavoring agents. The water soluble bulk portion dissipates over a period of time during chewing. The gum base portion is retained in the mouth throughout the chewing process.

The insoluble gum base generally includes elastomers, resins, fats, oils, waxes, softeners and inorganic fillers. The elastomers may include polyisobutylene, isobutylene-isoprene copolymer, styrene butadiene rubber and natural latexes such as chicle. The resins may include polyvinyl acetate and terpene resins. Low molecular weight polyvinyl acetate is a preferred resin. Fats and oils may include animal fats such as lard and tallow, vegetable oils such as soybean and cottonseed oils, hydrogenated and partially hydrogenated vegetable oils, and cocoa butter. Commonly used waxes include petroleum waxes such as paraffin and macrocrystalline wax, natural waxes such as beeswax, candellia, carnauba and polyethylene wax. The present invention contemplates the use of any commercially acceptable chewing gum base.

The gum base typically also includes a filler component such as calcium carbonate, magnesium carbonate, talc, dicalcium phosphate and the like; softeners, including glycerol monostearate and glycerol triacetate; and optional ingredients such as anti- oxidants, colors and emulsifiers. The gum base con¬ stitutes between 5-95% by weight of the chewing gum composition, more typically 10-50% by weight of the chewing gum, and most commonly 20-30% by weight of the chewing gum.

The water soluble portion of the chewing gum may include softeners, bulk sweeteners, high intensity sweeteners, flavoring agents and combinations thereof. Softeners are added to the chewing gum in order to optimize the chewability and mouth feel of the gum. The softeners, which are also known as plasticizers or plasticizing agents, generally constitute between about 0.5-15% by weight 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 constitute between 5-95% by weight of the chewing gum, more typically 20-80% by weight of the chewing gum and most commonly 30-60% by weight of the chewing gum. Bulk sweeteners may include both sugar and sugarless sweeteners and components. Sugar sweeteners may include saccharide containing components 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 components with sweetening charac¬ teristics but are devoid of the commonly known sugars. 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.

Dual morphology aspartame and, possibly, other high intensity sweeteners are present and are commonly used with sugarless sweeteners. The coated aspartame of the invention should be present in an amount such that the aspartame constitutes between 0.001-5% by weight of the chewing gum, preferably between 0.01-1% by weight of the chewing gum. Aspartame is about 180 times sweeter than sucrose. In addition to dual morphology aspartame, other high intensity sweeteners (which are defined as being at least 20 times sweeter than sucrose) may be employed in the chewing gum product. These may include but are not limited to sucralose, salts of acesulfame, alitame, saccharin and its salts, cyclamic acid and its salts, glycyrrhizin, dihydrochalcones, thaumatin, monellin, and the like, alone or in combination.

Combinations of sugar and/or sugarless sweeteners may be used in chewing gum. The sweetener may also function in the chewing gum in whole or in part as a water soluble bulking agent. Additionally, the softener may also provide additional sweetness such as with aqueous sugar or alditol solutions.

Flavoring agents should generally be present in the chewing gum in an amount within the range of about 0.1-15% by weight of the chewing gum, preferably between about 0.2-5% by weight of the chewing gum, most preferably between about 0.5-3% by weight of the chew¬ ing gum. Flavoring agents may include 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, spearmint oil, other mint oils, clove oil, oil of wintergreen, anise and the like. Artificial flavoring agents and components may also be used in the flavor ingredient of the invention. Natural and artificial flavoring agents may be combined in any sensorially acceptable fashion.

Optional ingredients such as colors, emulsi¬ fiers, pharmaceutical agents and additional flavoring 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 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 gum base may alternatively be melted in the mixer. Color 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. The encapsulated dual morphology aspartame of the invention, and flavoring 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 recognize that variations of this mixing procedure, or other mixing procedures, may be followed.

A wide range of changes and modifications to the embodiments of the invention described above will be apparent to persons skilled in the art. The following examples are not to be construed as imposing limitations on the invention, but are included merely to illustrate preferred embodiments.

EXAMPLE 1

Three hundred grams of Nutra*Sweet brand aspartame (a prior art aspartame) were dry blended with 53 grams of Dow E4M Premium Grade HPMC. A photomicrograph illustrating the cylindrical needle¬ like morphology of this aspartame is shown in FIG. 1(a). Two hundred twenty-five grams of water were added incrementally and blended over a 5 to 10 minute period. The damp mixture was then dried overnight in a convection oven set at 160^βF. The dried product was then ground using a hammer mill equipped with a 0.027 inch hole screen to yield 219.5 grams of granulated agglomerated aspartame. A photomicrograph illustrating the agglomerated ingredient is shown in FIG. 2(a).

EXAMPLE 2

The procedure of Example 1 was repeated except that Sanecta (fine powder grade) aspartame from the Holland Sweetener Company was used instead of the Nutrasweet aspartame. The Sanecta aspartame meets the dual morphological requirements of the present invention. A photomicrograph illustrating this dual morphology is shown in FIG. 1(b). A photomicrograph illustrating the agglomerated aspartame ingredient is shown in FIG. 2(b).

EXAMPLES 3 AND 4

Peppermint flavored chewing gum samples were prepared using the granulated coated aspartame ingredients of Examples 1 and 2 , according to the following formulae:

. .

*blend contains 68.5% hydrogenated starch hydrolysate solids , 25.0% glycerin and 7.5% water. The gum samples of Examples 3 and 4 were chewed by a panel of chewers for specified time periods after which the chewed cuds were collected and analyzed by high pressure liquid chromatography for residual aspartame content. Based on the initial content, the average percent aspartame remaining at each chewing time was:

Example 3 Example 4

Time (Min . ) (Comparative) ( Inventive )

0 100 100

2 75 90

4 70 67

10 25 38

20 <5 <5

In order to verify the results and determine the effects of aging, the gum samples of Examples 3 and 4 were tested in the same manner after four weeks of aging at 85 °F. The results were as follows:

Time (Min. )

0

2

4 10 20

It can be seen from the above data that the agglomerated dual morphology aspartame of the invention releases more slowly during chewing. Also, the improvement is maintained during storage of the chewing gum.

In order to compare the shelf stability, the gum samples of Examples 3 and 4 were remade and were stored in an oven at 85°F. The samples were removed from the oven at various times and analyzed for aspartame content by high pressure liquid chromatography. The analytical testing yielded the following results, expressed as a percentage of the initial aspartame remaining:

Time (Weeks)

0 2 4 8 16

Thus, the agglomerated dual morphology aspartame of the invention exhibited improved long-term shelf stability compared to the agglomerated aspartame of the prior art.

While the embodiments of the invention disclosed herein are presently considered to be preferred, various modifications and improvements can be made without departing from the spirit and scope of the invention. The scope of the invention is indicated in the appended claims, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.

Claims

WE CLAIM:

1. A stabilized high intensity sweetener ingredient, comprising: about 35 to about 95 weight percent aspartame; and about 5 to about 65 weight percent of a coating agent; the aspartame including about 65 to about 95 percent of a first morphological component A, about 5 to about 35 percent of a second morphological component B, and zero to about 10 percent of a third morphological component C, by weight of the aspartame; the morphological component A being characterized by micro-needles of aspartame having diameters ranging from less than one micron to about 3 microns and lengths ranging from about 2 microns to about 15 microns; the morphological component B being charac¬ terized by generally spherical particles of aspartame having diameters ranging from about 40 to about 200 microns; the morphological component C being characterized by particles of aspartame which do not have the morphology of either morphological component A or morphological component B.

2. The stabilized high intensity sweetener ingredient of claim 1, wherein the morphological component A constitutes about 75 to about 85 weight percent of the total aspartame.

3. The stabilized high intensity sweetener ingredient of claim 1, wherein the morphological component A constitutes about 80 weight percent of the total aspartame.

4. The stabilized high intensity sweetener ingredient of claim 1, wherein the morphological component B constitutes about 15 to about 25 weight percent of the total aspartame.

5. The stabilized high intensity sweetener ingredient of claim 1, wherein the morphological component B constitutes about 20 weight percent of the total aspartame.

6. The stabilized high intensity sweetener ingredient of claim 1, wherein the morphological component C constitutes about zero to about 5 weight percent of the total aspartame.

7. The stabilized high intensity sweetener ingredient of claim 1, wherein the morphological component C constitutes about zero weight percent of the total aspartame.

8. The stabilized high intensity sweetener ingredient of claim 1, comprising about 5 to about 50 weight percent of the coating agent and about 50 to about 95 weight percent of the aspartame.

9. The stabilized high intensity sweetener ingredient of claim 1, comprising about 10 to about 30 weight percent of the coating agent and about 70 to about 90 weight percent of the aspartame.

10. The stabilized high intensity sweetener ingredient of claim 1, wherein the coating agent comprises modified cellulose.

11. The stabilized high intensity sweetener ingredient of claim 1, wherein the coating agent comprises hydroxypropyl methylcellulose.

12. The stabilized high intensity sweetener ingredient of claim 1, wherein the coating agent comprises gum arabic.

13. The stabilized high intensity sweetener ingredient of claim 1, wherein the coating agent comprises shellac.

14. The stabilized high intensity sweetener ingredient of claim 1, wherein the coating agent comprises zein.

15. The stabilized high intensity sweetener ingredient of claim 1, wherein the coating agent comprises starch.

16. The stabilized high intensity sweetener ingredient of claim 1, wherein the coating agent comprises a maltodextrin.

17. The stabilized high intensity sweetener ingredient of claim 1, wherein the coating agent comprises lactose.

18. The stabilized high intensity sweetener ingredient of claim 1, wherein the coating agent comprises a carbohydrate.

19. The stabilized high intensity sweetener ingredient of claim 1, wherein the coating agent comprises a polymer selected from the group consisting of polyolefins, polyesters, polyvinyl acetate, and combinations thereof.

20. The stabilized high intensity sweetener ingredient of claim 1, further comprising about two to about three weight percent water.

21. A method of preparing a stabilized high intensity sweetener ingredient, comprising the steps of: providing a quantity of aspartame which includes about 65 to about 95 percent of a first morphological component A, about 5 to about 35 percent of a second morphological component B, and zero to about 10 percent of a third morphological component C, by weight of the aspartame; the morphological component A being characterized by micro-needles of aspartame having • diameters ranging from less than one micron to about 3 microns and lengths ranging from about 2 microns to about 15 microns; the morphological component B being characterized by generally spherical particles of aspartame having diameters ranging from about 40 to about 200 microns; the morphological component C being characterized by particles of aspartame which do not have the morphology of either morphological component A or morphological component B; blending the aspartame with about 5 to about 65 weight percent of a coating agent; blending a solvent with the aspartame and coating agent to form a damp mixture; drying the damp mixture to form a stabilized high intensity sweetener ingredient; and granulating the stabilized high intensity sweetener ingredient into particles.

22. The method of claim 21, wherein the coating agent comprises hydroxypropyl methylcellulose.

23. The method of claim 21, wherein the solvent comprises water.

24. The method of claim 22, wherein the solvent comprises water.

25. The method of claim 24, wherein the water comprises about 20 to about 55 weight percent of the damp mixture.

26. The method of claim 24, wherein the water comprises about 30 to about 40 weight percent of the damp mixture.

27. The method of claim 24, wherein the water comprises about 36 weight percent of the damp mixture.

28. The method of claim 23, wherein the water constitutes about 2 to about 3 weight percent of the stabilized high intensity sweetener ingredient after drying.

29. The method of claim 21, wherein the coating agent comprises zein.

30. The method of claim 21, wherein the solvent comprises ethanol.

31. The method of claim 29, wherein the solvent comprises ethanol.

32. The method of claim 31, wherein the ethanol constitutes about 25 to about 50 weight percent of the damp mixture.

^~33. The method of claim 21, wherein the coating agent comprises shellac.

34. The method of claim 33, wherein the solvent comprises ethanol.

35. The method of claim 21, wherein the aspartame and coating agent are dry blended together before the solvent is added.

36. The method of claim 21, wherein the solvent is added and blended in a plurality of increments.

37. The method of claim 21, wherein the drying is accomplished by spreading the damp mixture onto a pan and exposing the damp mixture to heat.

38. The method of claim 21, wherein the granulating step includes passing the stabilized high intensity sweetener ingredient through a screen.

39. The method of claim 38, wherein the screen has openings not larger than about 0.05 inches in diameter.

40. A stabilized high intensity sweetener ingredient produced according to the method of claim 21.

41. A chewing gum composition, comprising: a water soluble bulk portion; a water insoluble chewing gum base; one or more flavoring agents; and a stabilized high intensity sweetener ingredient which includes aspartame and about 5 to about 65 weight percent of a coating agent; the aspartame including about 65 to about 95 percent of a first morphological component A, about 5 to about 35 percent of a second morphological component B, and zero to about 10 percent of a third morphological component C, by weight of the aspartame; the morphological component A being charac¬ terized by micro-needles of aspartame having diameters ranging from less than one micron to about 3 microns and lengths ranging from about 2 microns to about 15 microns; the morphological component B being charac¬ terized by generally spherical particles of aspartame having diameters ranging from about 40 to about 200 microns; the morphological component C being charac¬ terized by particles of aspartame which do not have the morphology of either morphological component A or morphological component B.

42. The chewing gum composition of claim 41, wherein the stabilized high intensity sweetener ingredient comprises about 35 to about 99 weight percent of the coating agent and about 1 to about 65 weight percent of the aspartame.

43. The chewing gum composition of claim 41, wherein the stabilized high intensity sweetener ingredient comprises about 50 to about 95 weight percent of the aspartame and about 5 to about 50 weight percent of the coating agent.

44. The chewing gum composition of claim 42, comprising a sufficient amount of the stabilized high intensity sweetener ingredient that the aspartame comprises about 0.001 to about 5 weight percent of the chewing gum.

45. The chewing gum composition of claim 42, comprising a sufficient amount of the stabilized high intensity sweetener ingredient that the aspartame comprises about 0.01 to about 1 weight percent of the chewing gum.

46. The chewing gum composition of claim 41, wherein the coating agent comprises hydroxypropyl methylcellulose.

47. The chewing gum composition of claim 41, further comprising a second high intensity sweetener ingredient selected from the group consisting of sucralose, salts of acesulfame, alitame, saccharin and its salts, cyclamic acid and its salts, glycyrrhizin, dihydrochalcones, thaumatin, monellin, and combinations thereof.

48. A method of preparing a chewing gum, comprising the steps of: providing a stabilized high intensity sweetener ingredient which includes about 5 to about 65 weight percent of a coating agent and aspartame, the aspartame including about 65 to about 95 percent of a first morphological component A, about 5 to about 35 percent of a second morphological component B, and zero to about 10 percent of a third morphological component C, by weight of the aspartame; the morphological component A being charac¬ terized by micro-needles of aspartame having diameters ranging from less than one micron to about 3 microns and lengths ranging from about 2 microns to about 15 microns; the morphological component B being charac¬ terized by generally spherical particles of aspartame having diameters ranging from about 40 to about 200 microns; the morphological component C being charac¬ terized by particles of aspartame which do not have the morphology of either morphological component A or morphological component B; providing a water soluble bulk portion, a water insoluble chewing gum base, and one or more flavoring agents; adding the bulk portion, the chewing gum base, the one or more flavoring agents and the stabilized high intensity sweetener ingredient to a mixer; blending the components in the mixer to form a homogeneous gum mass; discharging the gum mass from the mixer; and forming the gum mass into chewing gum pieces.

49. The method of claim 48, wherein the stabil¬ ized high intensity sweetener ingredient is added to the bulk portion of the chewing gum.

50. A chewing gum prepared according to the method of claim 48.