CA1108004A - Food products for improved dental health - Google Patents

Abstract

ABSTRACT The addition of effective amounts of L-aspartyl-L-phenyl-alanine methyl ester (aspartame), to dental caries supporting food products reduces the tendency toward the occurrence of dental caries. Also, the addition of aspartame to low pH beverages reduces the tendency toward tooth enamel demineraliza-tion as well as dental caries.

Description

The present invention relates to dental health and food products, and specifically to the reduction of dental caries and tooth enamel demineralization caused by a wide variety of food products.
A number of food products have caused concern in recent years as being possibly related to decreased dental health in the persons consuming them. This concern has prompted a good deal of research to either prove or disprove the relationship, as well as research directed toward finding ways of eliminating the problems with respect to these products.
Principally cited as having possible connection with decreased dental health are foods high in acid and those high in sucrose content. Recent studies with rats, for e~ample, have indicated that continued consumption of low pH beverages, whether natural or artificial, can result in a generalized deminerali-zation of the teeth. In this regard, see for example: Wagg et al., British Dental Journal, vol. 119/ No. 3, pages 118 through 123, August 3, 1965; and McDonald Jr., et al., J. Dent. Res., March-April 1973, pages 211-216. Some investigators have indicated that certain phosphates, such as calcium phosphates may inhibit this form of demineralization or may, in fact, effect remineralization of teeth demineralized in this manner. In this regard, see for example: Wagg et al., supra; Picket et al., The Alabama Journal of Medical Sciences, vol. 2, no. 3, July 1965;
Silverstone et al., Caries Research, 5:323-342, 1971; and U.SO
Patent 3,375,168 to J. H. Curtin et al. Additives such as calcium phosphates have not, however, completely eliminated the problem.

While there is evidence on both sides of the question, it can be safely said that sucrose does, under many circumstances of use in fcod products, result in increased dental caries.
Exemplary of teachings of this kind is Scherp, Science, Vol. 173, No. 4003, pages 1199-1205. With all the discussion and research in this area, there is still a need for an additive which can mitigate the problem of dental caries caused by food products which have been identified as troublesome.
The present invention provides additives for food products which are effective to reduce the causation of dental caries and tooth enamel demineralization by food products which would normally foster these problems.
Thus, the instant invention entails adding an amount of L-aspartyl-L-phenylalanine methyl ester to a food product which would have the normal tendency toward demineralizing tooth enamel and/or fostering dental caries, said L~aspartyl-L~phenylalanine methyl ester having the ability to effect a rise in the pH of a dilutely acid aqueous solution, which amount is less than or greater than that amount which would provide a desired level of sweetness and reduce the tendency of the food product toward demineralizing tooth enamel and/or fostering dental caries.
More specifically, L-aspartyl-L-phenylalanine methyl ester (aspartame), is added to fcod compositions normally causative of dental caries or tooth enamel demineraliæation.
The L-aspartyl-L-phenylalanine methyl ester is added alone or in combination in any amount effective to cause a decrease in dental caries and/or tooth enamel demineralization over that which would normally occur when the food product is consumed.

The use of aspartame, which is well known as a sweetener (see for example U.S. Patent 3,642,491 to J. M. Schlatter), to provide food products of improved dental health is believed new and should be effective over a wide range of concentrations in the food products. Specifically, preferred concentrations for aspartame are those above and below the levels thought by those skilled in the art to provide desirable levels of sweetness.
However, the invention envisa~es all novel levels of aspartame in food products where they are present, alone or in combination, in amounts effective to mitigate the causation of dental caries and/or tooth enamel demineralization over that which would normally occur. Where sucrose is the cariogenic agent, amounts of aspartame within the range of ~rom abou~ 0.1 to 10 parts of aspartame for each lOn parts oE sucrose are believed effective.
Within the conception of the present invention is L-aspartyl-L-phenylalanine methyl ester which effects a rise in the pH of a dilutely acid (e.g., pH 2-5) a~ueous solution.
Specifically useful is aspartame.
The types of products in which L-aspartyl-L-phenyl-alanine methyl ester can be employed for its advantageous effect on dental health are broad and its effectiveness according to this invention is not presently known to be limited by any actors present in food products. A representative listing of the various food products which can advantageously enjoy the benefits of the present invention is as Eollows:
Bread Breakfast Cereals Cakes Candies Carbonated Beverages Chewing Gum Chocolates Coffee L~ghteners Cookies Dry Beverage Mixes F~rinaceous Snack Items Flavoxed ~ces Frostings Frui~ Concentrates Fruits Dessexts Xce C~eam Juices Puddings ~herbets Syrups Table Sug~r Whipped Toppings As indicated r this lis~ is merely representative and is not exhaustive of the` types of food products contemplated herein.
~0 While the scope of products which can be improved by the present invention is broad, the following disclosure will relate specifically to a lo~ p~ beverage mix. This product is dealt with as only exemplary and should not be taken as limiting of the invention.
In the low pH beverage products as with the other products encompassed by the presen~ invention, the amount of L-aspartyl-L-phenylalanine methyl ester employed can be any amount which is effective to attain the objects of the invention.
Preferably, however, aspartame is employed at a level insuficient by itsel~ to provide a desirable sweet beverage or at a le~Tel greater than that necessary, when used alone or in comhination with another sweetener, to provide the desirable sweetness in the beverage. While these variations in level of ~weetne$s from conventional beverages may at first seem unusual to the consumer, it is believed that the improvement in dental health achieved over conventional beverages should outweigh any ~dverse reaction in this regard.

For the purpose'of t~e present invention ~ low ~H
beverage is define~ as Qne having ~n acid p~ e,g., below about 6 and preferably beIo~ about 5, and containi~g from about ~.015 to about 0.15 gram equivalents of ~n edible acid pex ~uart of ;
beverage.
Beverage~ of this type are well known and typ~Gally comprise an aqueous solution of a flavorant, a colorant, a sweet-ener, a food acidulent. ~lso, these beverages can contain bufers to control acidity, ~ums to provide texture and clouding compo-sitions to pro~ide a degree`o~ opacity to the beverage. Beveragesof this kind can also include var;ous food and nutritional supplements such as vitamins and minerals. Vltamins A and C are typical of such additives.
Typicàl of the edible acids ~hich can be employed are citric, malic, adipic and fumaric acids. These acids can be employed alone or in combination and can be supplemented or replaced by other conventional food acidulents.
A wide variety of fla~orants are known for use in beverages of the kind considered here. Typical of these are ~o natural and artificial flavorants such as cherry, strawberry, grape, orange, lemon, lime, root beer, cola, raspberry, ~rapefruit, fruit punch, and the like, which are employed in suitably effective amounts.
Apart from the asp~rtame which has a sweetening effect at known concentrations, ~ut ~hich i$ not employed according to the present in~ention primarily ~s a,s~eetener, sweetness can be obtained using any of the known,,edibIe natural or synthetic sweeteners.

.

The aspartame is employed to effect the objects of the present inVention at levels of fro~ about Q~25 to ab~ut 2.Q0 grams per quart of beverage or an amount of dry mîx for preparing the same. Prefera~ly .it ~5 employed at levels o from ~bout 0.50 to about ~75 ~rams per quart of bever~ge or mix therefor.
One'preferred beverage contains a less than sweetening amount of aspartame ~long with sucrose in a sweetening amount, e.g., about 25 to about 100 grams of sucrose per quart of bevexage or mix therefor, and from about ~.25 to about 0.50 grams of aspartame per quart of beverage, the beverage, thus, having a total amount of sweetener greater than would be normally desired.
This beverage preferably contains from'0.015 to 0.08 gram equivalents of acid per quart of beverage. In this embodiment, the caloric value'of the' sucrose is present in the beverage, but the cariogenic propensities thereof are reduced, not only due to the reduced leveI of sucrbse added, but also due to the protective - ' effect of the aspartame. The excess sweetness can be reduced, if desired, by adding to the beverage a sweetness modulating ;~
material such as alum, naringin, or the like. ' The ingredients are preferably dry blended to form the mix and can be agglomerated, as by steam agglomeration, if desired.
The mix ingredients are preferably packaged by volumetric metering devices into conventional plastic coated foil packs to preserve freshness.
The follo~in~ specific examples are presented for the purpose of further illustrating the pxesent invention, and are not to be taken as limiting in any re~ard~ Unless other~ise indicated, all parts and percentages-are by weight.

" , ,; , '; ., : ' ~XAMPT,E I `~
~ xelativel~ low :acid inst~nt beverage m~x ~cco~ding to the Pxesent invention is pxepared by dry mixing ~he following material5:
In~redients Parts Citric acid, anhydrous Monocalcium Phosp~ate 34.3 Aspartame 12,6 Carrier for aspartame (hydrolyzed cereal solids~ 8,4 Flavorant 1.8 Vitamin C 1~3 Colorant 0,5 Vitamin A a. 14 About 4.4 grams of this mix are added to a quart of water to provide a pleasing beverage ha~ing the advantages of ~.
the present invention.
EXAMPLE II
A beverage mix having a slightly higher acid con~ent than that of Example I is prepared by dry mixing ~he following ingredients:
Ingre~ients Parts Citric acid, anhydrous 57.5 Monocalcium Phosphate 16~4 Trisodium Citrate 8.8 Aspartame 5,5 Carrier for ~spartame (hydrolyzed cereal solids~ 1.8 Flavorant 6,0 Clouding composition 3.3 Vitamin C 0.6 Vitamin A 0.07 About 9 grams of this mix are added to a quart o water to provide a pleasing beverage having the advantages of the present invention.
EXAMPLE III
A further beverage mix, having a relatively high acid content, is prepared by dry mixing the following ingredients:
Ingredlents Parts Dextrin 58.4 Aspartame 1.8 Citric Acid 19.0 Clouding composition 5.6 Monocalcium Phosphate 4.0 Potassium Citrate 2.8 Tricalcium Phosphate 2.4 Vitamin C 1.5 Orange Flavorant 2.6 Vegetable Gum 1.8 Vitamin A 0.1 Color 0.15 About 34 grams of this mix are added to a quart of water to provide a pleasing simulated orange juice having the advantages of the present invention.
EXAMPLE I~
A gelatin dessert mix is prepared by dry mixing the following ingredients:

. . . ..

Ing~edients Parts Gelatin 55,6 Adipic ~cid 23.3 Fumaric Acid 2.6 Potassium Citrate 9~4 Stra~berry Flavor5 -Eixed in vegetable ~um 1~0 Strawberry Color fixed in vegetable gum 0.3 Aspartame 7~9 About 13 grams of this mix are dissolved in one cup of boiling water by stirring. One cup of cold water is then added and mixed. The total solution is then chilled to set the gelatin, thereby providing a strawberry flavored gelatin dessert having the benefits of the present in~ention.
EX~MPLE V
An improved table sugar is obtained by mixing 1.0 parts of aspartame according to the present invention with about 100 parts of sucrose. If desired, the aspartame can be sprayed on in an aqueous solution while subjecting the sucrose to tumbling in drying air.
- EXAMPLE VI
A liquid coffee lightener ~s prepared from the following ingredients:
~ngredients Parts Sucrose 46.6 Hydrogenated Coconut Oil 25~0 ~ater 23.4 Sodium stearoyl-2-lactylate 5.0 Aspartame 0.5 _ g _ The coffee lightener is prepared by first blending 233 g of sucrose with 25 g of finely ground sodium stearoyl~2-lactylate in a blender for 10 minutes. This mixture is then added slowly to 117 ml of tap water. The water is stirred gently and held at 120F. ~fter about 10 minutes of ~tirring, the sodium stearoyl-

2-lactylate is e~enly dispersedO This dispersion is then transerred to a W~RING BLENDOR* and 125 g of hydrogenated coconut oil at 120 is added. Blending at high speed is continued for 10 minutes at which point the emulsion temperature reaches 160F. Upon cooling to room temperature, it gradually loses air to give a translucent pourable emulsion of low viscosity. Upon dilution with distilled water, the dilute emulsion is opaque and has a pH of 6.7. The undiluted emulsion has a water activity of 0.80. This coffee lightener is used in the same manner as cream.
EXAMPLE VII
A dried coffee lightener is prepared by employing the same procedure as that in Example VI but substituting a combination of 40 parts 42 D.E. hydrolyæed cereal solids 2 parts sodium caseinate and 1 part vegetable gum for the sucrose, and spray drying the emulsion.
EXAMPLE VIII
A two-week rat feeding study was conducted with male Caesarean-derived Sprague-Dawley rats approximately 200 grams in body weight using the following protocol.
The animals were fed a standard animal chow diet ad libitum throughout the study. They were housed individually in open mesh stainless steel suspended cages in an air conditioned room with the temperature controlled in the range 75F. + 3F.
Fifteen rats were randomly assigned to each test group after blocking on body weightr The following lo~ pH test beverages were fed to the various test groups:
(Il low pH grape flavored be~erage havin~ the following ~ormulation: :
. Gxams ~er 1 quart Dry Ingredients of ~eVera~e Citric Acid 1.8 Monocalcium Phosphate 1.5 Grape Flavor Q,075 ~scorb~c ~cid 0.055 Grape Shade 0.023 Vitamin A 0.006 Aspartame 0.55 (2) beverage (1) with 100 gxams of sucrose per quart of beverage in place of of the aspartame;

(3) beverage (1~ without monocalcium phosphate, but containing an additional 0.2 grams per quart of citric acid to balance the taste and tartness due to the removal of the monocalcium phosphate;
(4~ beverage`(~ with 100 grams of sucrose per quart of beverage in place of the`aspartame; and (5) deionized water.
After the two week feediny period the rats were ::
sacrificed by decapitation and then the heads were defleshed by scrubbing with`a toothbrush ate~ an autoclavin~ procedure for 20 minutes at 15 pounds pressure.
The mandibular molaxs were stained by.placin~ them in a 0.125% alcoholic solution of ~lizarin Red S, rinsed with water and dried in a hot air oven at 150F.

After the staining process was completed the linyual surfaces of the molars were scored for the extent of tooth enamel demineralization using a modification of the scoring scale developed by Restarski, Science, Vol. 102: 404-40s, 1945.
Before scoring with the aid of a binocular microscope at 13X
the molars were assigned random numbers.
The up-take of stain and the extent of ridging were to estimate the amount of tooth enamel demineralization for each mandibular molar using the following grading scale with an increase in severity:
0 ~ No demineralization - no detactable lingual stain 1 - Slight demineralization - slight stain 2 - Mild demineralization - moderate stain 3 - Moderate demineralization - slight ridging, strong stain

4 - Moderate demineralization - moderate ridging, 1/3 of dentin exposed

5 - Strong demineralization - strong ridging, 1/3 to 2/3 of dentin exposed

6 - Strong demineralization - very strong ridging, greater than 2/3 of dentin exposed.
The results are summarized in the following table:
Tooth Enamel Demineralization % Decrease Due Beverage Score to Aspartame 2 1.5 --1 0.8 47 4 3.5 __ 3 2.5 ~9 0.2 __ .

Due to the fact that the aspartame can degrade in aqueous system to diketopiperazine and mixtures of dikeiopipera-zine, aspartic acid and phenylalanine, it is suggested that the breakdown products of aspartame are similarly effective ln im-proving dental health as is the aspartame.
EXAMPLE IX
A 60-day rat Eeeding study was conducted with weanling Caesarean-derived male wistar caries-susceptible rats using the following protocol:
The test group were fed semi-synthetic diets containing 5% alpha-cellulose, 20% lactalbumin, 3% corn oil, 1% Association of Official Analytical Chemists vitamin mix and 3% of a Massachusetts Institute of Technolog~ 200 mineral mix modified to contain 30% dicalcium phosphate. The remaining 68% of the diet consisted of either 68% confectionary 10X sucrose or coated corn flakesc The animals were housed in open mesh stainless steel suspended cages in an air conditioned room with the temperature controlled in the range of 75F. ~ 3F. Fifteen rats were randomly assigned to each treatment after blocking on body weight.
After the termination of the study, the heads of the animals were autoclaved at 15 pounds pressure for 15 minu-tes and then the mandibles were removed and cleaned with a coarse bristle toothbrush. After the mandibles are dried, they are stained with 0.0208% murexide in 70% ethanol. After -the mandibles are revised and dried, they are scored for caries ~:2 ~ .

using a modification of the Keyes method in J. Dental Research 37, 1088-99 (1958). The caries scores are a combination of -the occlusal and smooth surface caries severity scores on the nlandibular molars using scores of 0, 1, 2 and 3 for designating severity of the lesions.
The following treatments were included in the study:
1) beverage (1) con-taining aspartame described in Example VIII as the drinking fluid and the semi-synthetic diet containing 68% confectionary lOX sucrose as the carbohydrate.
2) beverage (2) containing sucrose described in Example VIII as the drinking fluid and the semi-synthetic diet containing 68~ confectionary lOX sucrose as the carbohydrate.
3) distilled water as the drinking fluid and the semi-synthetic diet containing 68% corn flakes containing 0.3 aspartame.
4) distilled water as the drinking fluid and the semi-synthetic diet containing 68% corn flakes with a 40% sucrose syrup coating in place of the aspartame.
The results are summarized in the following table:
Caries Severit~ Scores Decrease Due Treatment Score to Aspartame 2 11.4 --1 7.0 39 4 3.3 __ 3 1.7 48 EXAMPLE X
A 60-day rat feeding study was conducted with weanling Caesarean-derived male caries-susceptible rates. The protocol was identical to that described in Example IX with the ex-ceptions that casein was substituted for lacta]bumin as the source of protein and the dicalcium phospha-te level in the Massachusetts Institute of Technology 200 salt mix 3L~ ~r ~

was decreased to 27.5%. Distilled water was provided as the drinking fluid. The aspartame in the diet replaced part of the alpha cellulose.
The following dietary treatments were included in the study:
1) Basal cariogenic diet containing 68% confectionary lOX sucrose.
2) Same as treatment (1) with 0.341% aspartame.
The results summarized in the following table:
Caries~Severity Scores % Decrease Due Treatment Score to As~ rtame 1 15.5 --2 11.6 25 The above disclosure has provided a description of the invention for the purpose of enabling the person skilled in the art how to make and use the same and has not been made for the purpose of detailing all things known or obvious to the skilled worker. Upon reading this disclosure, many modifications and variations of this invention will become apparent to those skilled in the art. It is intended that all such modifications and variations be included within the scope of the present invention which is defined by the claims,

Claims (7)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. Method of reducing the tendency of a beverage containing from about 25 to about 100 grams of sucrose and from about 0.015 to 0.15 gram equivalents of an edible food acid per quart of beverage towards demineralizing tooth enamel and/or fostering dental caries, comprising adding to each quart of the beverage from about 0.25 to about 2.00 grams of 2-aspartyl-L-phenylalamine methyl ester.

2. Method according to claim 1, wherein the 2-aspartyl-L-phenylalamine methyl ester is added in amounts of from about .50 to about 0.75 grams per quart of beverage.

3. A beverage containing from about 25 to about 100 grams of sucrose and from about 0.015 to 0.15 gram equivalents of an edible food acid per quart of beverage and containing from about 0.25 to about 2.00 grams of L-aspartyl-L-phenylalamine methyl ester per quart of beverage when prepared according to the method of claim 1.

4. Method of preparing a beverage mix containing water and an edible food acid in an amount sufficient to pro-vide an admixture with the water from 0.015 to 0.15 gram equiv-alents of the edible food acid per quart of beverage, and a sweetener in an amount providing the beverage mix with normally acceptable sweetening, comprising adding L-aspartyl-L-phenylalamine methyl ester in an amount to provide an admixture with the water from 0.25 to 2.0 grams of the L-aspartyl-L-phenylalamine methyl ester per quart of beverage, the amount of L-aspartyl-L-phenylalamine methyl ester reducing the tendency of the beverage toward demineralizing tooth enamel and/or fostering dental caries.

5. A method according to claim 4, wherein the sweet-ener is sucrose present in amounts from about 25 to about 100 grams per quart of beverage.

6. A beverage mix containing water and an edible food acid in an amount sufficient to provide an admixture with the water from 0.015 to 0.15 gram equivalents of the edible food acid per quart of beverage and a sweetener providing the beverage mix with normally acceptable sweetening, and also additionally containing from 0.25 to 2.0 grams of L-aspartyl-L-phenylalamine methyl ester per quart of beverage, the amount of L-aspartyl-L-phenylalamine methyl ester reducing the tendency of the beverage toward demineralizing tooth enamel and/or fostering dental caries when prepared according to the method of claim 4.

7. A beverage mix according to claim 6, wherein the sweetener is sucrose present in amounts from about 25 to about 100 grams per quart of beverage.