STEVIA COMPOSITION

Abstract

Stevia compositions are prepared from steviol glycosides of Stevia rebaudiana Bertoni. The compositions are able to provide a superior taste profile and can be used as sweetness enhancers, flavor enhancers and sweeteners in foods, beverages, cosmetics and pharmaceuticals.

Claims

1. A process for producing a rebaudioside B composition, comprising the steps of: providing a Stevia sweetener comprising rebaudioside A having a carbohydrate residue at a C19 position; providing an alkaline aqueous solution free of any co-solvents; hydrolyzing the C19 carbohydrate residue of rebaudioside A to form rebaudioside B by dispersing the Stevia sweetener in the alkaline aqueous solution and incubating for about 0.5 to 48 hours at about 30-100° C. to form a mixture; cooling the mixture to about 10-30° C.; adjusting the pH with acid to about pH 3.0-4.0 to obtain a precipitate; separating the precipitate and washing it with water; and drying the washed precipitate to obtain the rebaudioside B composition; wherein the rebaudioside B composition comprises a mixture of rebaudioside A and rebaudioside B at a ratio of about 5%:95% to about 95%:5% (w/w).

2. The process of claim 1 further comprising the steps of: suspending the Stevia composition in water and incubating at an elevated temperature for about 1-3 hours; separating the Stevia composition from the water and drying the Stevia composition to obtain a purified Stevia composition; wherein the purified Stevia composition comprises rebaudioside B with greater than about 99% purity.

3. The process of claim 1 further comprising the steps of: suspending the rebaudioside B composition in water to form a suspension; increasing the temperature of the suspension by a gradient heating method; holding the suspension at an elevated temperature; decreasing the temperature of the suspension by a gradient cooling method to obtain a high stability and high concentration rebaudioside B composition solution; and spray drying the high stability and high concentration rebaudioside B composition solutionto provide an amorphous, highly soluble rebaudioside B composition powder.

4. The process of claim 1 wherein the Stevia sweetener comprises rebaudioside A.

5. A Stevia composition made by the process of claim 1, the composition comprising a mixture of rebaudioside A and rebaudioside B at a ratio of about 5%:95% to ab out 95%:5% (w/w).

6. The process of claim 3, wherein the Stevia composition comprises a mixture of rebaudioside A and rebaudioside B at a ratio of about 5%:95% to about 95%:5% (w/w).

7. A process of claim 3, wherein the Stevia composition comprises a mixture of rebaudioside D and rebaudioside B at a ratio of about 5%:95% to about 95%:5%.

8. A sweetener composition comprising a rebaudioside B composition made by the process of claim 1 and an additional sweetening agent selected from the group consisting of: Stevia extract, steviol glycosides, stevioside, rebaudioside A, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside E, rebaudioside F, dulcoside A, steviolbioside, rubusoside, other steviol glycosides found in Stevia rebaudiana Bertoni plant and mixtures thereof, Luo Han Guo extract, mogrosides, high-fructose corn syrup, corn syrup, invert sugar, fructooligosaccharides, inulin, inulooligosaccharides, coupling sugar, maltooligosaccharides, maltodextins, corn syrup solids, glucose, maltose, sucrose, lactose, aspartame, saccharin, sucralose, sugar alcohols, and a combination thereof.

9. A flavor composition comprising a rebaudioside B composition made by the process of claim 1 and an additional flavoring agent selected from the group consisting of: lemon, orange, fruit, banana, grape, pear, pineapple, mango, bitter almond, cola, cinnamon, sugar, cotton candy, vanilla, and a combination thereof.

10. A food ingredient comprising a rebaudioside B composition made by the process of claim 1 and an additional food ingredient selected from the group consisting of: acidulants, organic and amino acids, coloring agents, bulking agents, modified starches, gums, texturizers, preservatives, antioxidants, emulsifiers, stabilisers, thickeners, gelling agents, and a combination thereof.

11. A food, beverage, cosmetic or pharmaceutical product comprising a rebaudioside B composition made by the process of claim 1.

12. A rebaudioside B composition comprising a mixture of rebaudioside A and rebaudioside B at a ratio of about 5%:95% to about 95%:5% (w/w).

13. A food, beverage, cosmetic or pharmaceutical product comprising the Stevia composition of claim 12.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are included to provide a further understanding of the invention. The drawings illustrate embodiments of the invention and together with the description serve to explain the principles of the embodiments of the invention.

[0027] FIG. 1 shows the chemical structure of rebaudioside A.

[0028] FIG. 2 shows the chemical structure of rebaudioside B

[0029] FIG. 3 shows an HPLC chromatogram of a Stevia composition comprising rebaudioside A and rebaudioside B.

DETAILED DESCRIPTION OF THE INVENTION

[0030] Advantages of the present invention will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

[0031] Rebaudioside A commercialized by PureCircle Sdn. Bhd. (Malaysia), containing, rebaudioside A (about 95-100%), stevioside (about 0-1%), rebaudioside C (about 0-1%), rebaudioside D (about 0-1%), rebaudioside F (about 0-1%), rebaudioside B (about 0.1-0.8%) and other glycosides amounting to total steviol glycosides' content of at least about 95%, was used as a starting material. Alternatively Stevia extracts with different ratio of steviol glycosides may be used as starting materials.

[0032] The HPLC analysis of the raw materials and products was performed on an Agilent Technologies 1200 Series (USA) liquid chromarograph, equipped with Phenomenex Prodigy ODS3, 5 μm (4.6×250 mm) column at 40° C. The mobile phase was 32:68 mixture of acetonitrile and 10 mmol/L sodium phosphate buffer (about pH 2.6) at 1 mL/min. A diode array detector set at 210 nm was used as the detector.

[0033] In one embodiment of the invention, reb A was dispersed in aqueous alkaline solution. The concentration of reb A is about 0-50% (w/v) preferably about 10-25%. The preferred alkaline agents include KOH and NaOH however other agents capable of increasing the pH of the media above about pH 7 may be used as well. The concentration of alkaline agents were about 0.05-2.0M, preferably about 0.1-1.0M. The mixture was incubated at about 10-150° C., preferably about 30-100° C., for a period of about 0.5-48 hrs, preferably about 1-24 hrs. As a result reb A is hydrolyzed to reb B. The molar yield of conversion of reb B is about 5-100%, preferably about 10-90%.

[0034] After the reaction, the alkaline agent is neutralized by an acid, preferably by sulfuric acid or ortho-phosphoric acid until a pH of about 3.0-5.0 is reached, preferably until a pH of about 3.0-4.0 is reached. Upon neutralization, a precipitate is formed. The precipitate is separated by any method known in the art such as filtration or centrifugation and washed with water until the water reaches a pH of about 4.0-5.0. The obtained crystalline material is dried under vacuum at about 60-105° C. to yield a mixture of reb A and reb B with ratio of about 5%:95% to about 95%:5%, preferably about 50%:50% to about 90%:10%.

[0035] In another embodiment, the separated precipitate is suspended in water and the mixture is subjected to continuous agitation over about 0.5-24 hrs, preferably about 1-3 hours, at about 50-100° C., preferably about 60-80° C. The ratio of precipitate to water (w/v) is about 1:5 to about 1:20, preferably about 1:10 to about 1:15. The washed crystals are separated and dried under vacuum at about 60-105° C. to yield reb B with about 99% purity.

[0036] In one embodiment the obtained compositions have a water solubility of less than about 0.2% (w/v). The compositions were combined with the water at ratio of about 1:1 (w/w) and the obtained mixture was further subjected to a gradient heat treatment which resulted in a high stability and high concentration solution. The gradient of about 1° C. per minute was used in heating the mixture. The mixture was heated to the temperature of about 110-140° C., preferably about 118-125° C. and was held at maximum temperature for about 0-120 min, preferably about 50-70 min. After the heat treatment, the solution was cooled down to room temperature at gradient of about 1° C. per minute. The solution was spray dried by a laboratory spray drier operating at about 175° C. inlet and about 100° C. outlet temperatures. An amorphous form of the composition was obtained with greater than about 20% solubility in water at room temperature.

[0037] The compositions can be used as sweetness enhancer, flavor enhancer and sweetener in various food and beverage products. Non-limiting examples of food and beverage products include carbonated soft drinks, ready to drink beverages, energy drinks, isotonic drinks, low-calorie drinks, zero-calorie drinks, sports drinks, teas, fruit and vegetable juices, juice drinks, dairy drinks, yoghurt drinks, alcohol beverages, powdered beverages, bakery products, cookies, biscuits, baking mixes, cereals, confectioneries, candies, toffees, chewing gum, dairy products, flavored milk, yoghurts, flavored yoghurts, cultured milk, soy sauce and other soy base products, salad dressings, mayonnaise, vinegar, frozen-desserts, meat products, fish-meat products, bottled and canned foods, tabletop sweeteners, fruits and vegetables.

[0038] Additionally the compositions can be used in drug or pharmaceutical preparations and cosmetics, including but not limited to toothpaste, mouthwash, cough syrup, chewable tablets, lozenges, vitamin preparations, and the like.

[0039] The compositions can be used “as-is” or in combination with other sweeteners, flavors and food ingredients.

[0040] Non-limiting examples of sweeteners include steviol glycosides, stevioside, rebaudioside A, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside E, rebaudioside F, dulcoside A, steviolbioside, rubusoside, as well as other steviol glycosides found in Stevia rebaudiana Bertoni plant and mixtures thereof, Stevia extract, Luo Han Guo extract, mogrosides, high-fructose corn syrup, corn syrup, invert sugar, fructooligosaccharides, inulin, inulooligosaccharides, coupling sugar, maltooligosaccharides, maltodextins, corn syrup solids, glucose, maltose, sucrose, lactose, aspartame, saccharin, sucralose, sugar alcohols.

[0041] Non-limiting examples of flavors include lemon, orange, fruit, banana, grape, pear, pineapple, bitter almond, cola, cinnamon, sugar, cotton candy, vanilla flavors.

[0042] Non-limiting examples of other food ingredients include flavors, acidulants, organic and amino acids, coloring agents, bulking agents, modified starches, gums, texturizers, preservatives, antioxidants, emulsifiers, stabilisers, thickeners, gelling agents.

[0043] The following examples illustrate various embodiments of the invention. It will be understood that the invention is not limited to the materials, proportions, conditions and procedures set forth in the examples, which are only illustrative.

EXAMPLE 1

Preparation of Stevia Composition

[0044] 100 g of rebaudioside A produced by PureCircle Sdn. Bhd. (Malaysia), containing, 98.1% rebaudioside A, 0.3% stevioside, 0.2 rebaudioside C, 0.2% rebaudioside F, 0.4% rebaudioside B and 0.6% rebaudioside D was dispersed in 1000mL aqueous KOH (1M) and incubated at 50° C. for 2 hours. The mixture temperature was decreased to 20° C. and the pH was adjusted to pH 4.0 with sulfuric acid. The solution was held under moderate agitation conditions for 4 hours and a precipitate was formed. The precipitate was filtered and washed on the filter with 2000 mL of water. The washed crystals were dried under vacuum to yield 86g material containing about 84% reb A and 16% reb B. The water solubility (at 25° C.) of obtained material was about 0.2% (w/v).

EXAMPLE 2

Preparation of Stevia Composition

[0045] 100 g of rebaudioside A produced by PureCircle Sdn. Bhd. (Malaysia), containing, 98.1% rebaudioside A, 0.3% stevioside, 0.2 rebaudioside C, 0.2% rebaudioside F, 0.4% rebaudioside B and 0.6% rebaudioside D was dispersed in 1000 mL aqueous KOH (1M) and incubated at 80° C. for 5 hours. The mixture temperature was decreased to 20° C. and the pH was adjusted to about pH 4.0 with sulfuric acid. The solution was held under moderate agitation conditions for 4 hours and a precipitate was formed. The precipitate was filtered and washed on the filter with 2000 mL of water. The washed crystals were dried under vacuum to yield about 75 g material containing about 9% reb A and about 91% reb B. The water solubility (at 25° C.) of obtained material was about 0.1% (w/v).

EXAMPLE 3

Preparation of Stevia Composition

[0046] 100 g of rebaudioside A produced by PureCircle Sdn. Bhd. (Malaysia), containing, 98.1% rebaudioside A, 0.3% stevioside, 0.2 rebaudioside C, 0.2% rebaudioside F, 0.4% rebaudioside B and 0.6% rebaudioside D was dispersed in 1000 mL aqueous KOH (1M) and incubated at 80° C. for 7 hours. The mixture temperature was decreased to 20° C. and the pH was adjusted to about pH 4.0 with sulfuric acid. The solution was held under moderate agitation conditions for 3-4 hours and a precipitate was formed. The precipitate was filtered and washed on the filter with 2000 mL of water. The washed crystals were dried under vacuum to yield about 71 g material containing about 99.1% reb B. The water solubility (at 25° C.) of obtained material was about 0.1% (w/v).

EXAMPLE 4

Preparation of Stevia Composition

[0047] 75 g of material prepared according to EXAMPLE 2 was suspended in 1000 mL water. The mixture temperature was increased to 70° C. The suspension was held under moderate agitation conditions for 4 hours. The crystals were filtered and dried under vacuum to yield about 65 g material containing about 99.0% reb B. The water solubility (at 25° C.) of obtained material was about 0.1% (w/v).

EXAMPLE 5

Preparation of Soluble Stevia Composition

[0048] 50 g material prepared according to EXAMPLE 1 was mixed with 50 g of water and incubated in thermostatted oil bath. The temperature was increased at 1° C. per minute to 121° C. The mixture was maintained at 121° C. for 1 hour and then the temperature was decreased to room temperature (25° C.) at 1° C. per minute. The solution was dried using YC-015 laboratory spray drier (Shanghai Pilotech Instrument & Equipment Co. Ltd., China) operating at 175° C. inlet and 100° C. outlet temperature. About 47 g of an amorphous powder was obtained with about 25% (w/v) solubility in water (at 25° C.).

EXAMPLE 6

Preparation of Soluble Stevia Composition

[0049] 42 g of reb A produced by PureCircle Sdn. Bhd. (Malaysia) with purity of 99.2% (dry basis) and 8 g of reb B prepared according to EXAMPLE 4 were mixed with 50 g of water and incubated in thermostatted oil bath. The temperature was increased at 1° C. per minute to 121° C. The mixture was maintained at 121° C. for 1 hour and then the temperature was decreased to room temperature (25° C.) at 1° C. per minute. The solution was dried using YC-015 laboratory spray drier (Shanghai Pilotech Instrument & Equipment Co. Ltd., China) operating at 175° C. inlet and 100° C. outlet temperature. About 48 g of an amorphous powder was obtained with about 1.5% (w/v) solubility in water (at 25° C.).

EXAMPLE 7

Low-Calorie Orange Juice Drink

[0050] Orange concentrate (35%), citric acid (0.35%), ascorbic acid (0.05%), orange red color (0.01%), orange flavor (0.20%), and 0.05% Stevia composition, were blended and dissolved completely in water (up to 100%) and pasteurized. The Stevia composition was selected from a commercial Stevia extract (containing stevioside 26%, rebaudioside A 55%, and 16% of other glycosides), a commercial rebaudioside A (containing 98.2% reb A) or material obtained according to EXAMPLE 5.

[0051] The sensory evaluations of the samples are summarized in Table 1. The data shows that the best results can be obtained by using the composition obtained according to EXAMPLE 5. Particularly the drinks prepared with said composition exhibited a rounded and complete flavor profile and mouthfeel.

TABLE-US-00001 TABLE 1 Evaluation of orange juice drink samples Comments Sample Flavor Aftertaste Mouthfeel Stevia Sweet, licorice Bitterness Not Extract notes and aftertaste acceptable Reb A Sweet, slight Slight bitterness Not licorice notes and aftertaste acceptable EXAMPLE 5 High quality Clean, no bitterness Full sweetness, pleasant and no aftertaste taste similar to sucrose, rounded and balanced flavor

[0052] The same method can be used to prepare juices and juice drinks from other fruits, such as apples, lemons, apricots, cherries, pineapples, mangoes, etc.

EXAMPLE 8

Zero-Calorie Carbonated Beverage

[0053] A carbonated beverage according to formula presented below was prepared.

TABLE-US-00002 Quantity, % Ingredients Stevia Extract Reb A EXAMPLE 5 Cola flavor 0.340 0.340 0.340 ortho-Phosphoric acid 0.100 0.100 0.100 Sodium citrate 0.310 0.310 0.310 Sodium benzoate 0.018 0.018 0.018 Citric acid 0.018 0.018 0.018 Stevia composition 0.050 0.050 0.050 Carbonated water to 100 to 100 to 100

[0054] The sensory properties were evaluated by 20 panelists. The results are summarized in Table 2.

TABLE-US-00003 TABLE 2 Evaluation of zero-calorie carbonated beverage samples Number of panelists detected the attribute Taste attribute Stevia Extract Reb A EXAMPLE 5 Bitter taste 15 10 0 Astringent taste 16  9 0 Aftertaste 14 12 0 Comments Quality of sweet taste Bitter aftertaste Bitter aftertaste Clean (15 of 20) (10 of 20) (20 of 20) Overall evaluation Satisfactory Satisfactory Satisfactory (1 of 20) (5 of 20) (20 of 20)

[0055] The above results show that the beverages prepared using the composition obtained according to EXAMPLE 5 possessed the best organoleptic characteristics.

EXAMPLE 9

Diet Cookies

[0056] Flour (50.0%), margarine (30.0%) fructose (10.0%), maltitol (8.0%), whole milk (1.0%), salt (0.2%), baking powder (0.15%), vanillin (0.1%) and different Stevia compositions (0.03%) were kneaded well in dough-mixing machine. The obtained dough was molded and baked in oven at 200° C. for 15 minutes. The Stevia compositions were selected from a commercial Stevia extract (containing stevioside 26%, rebaudioside A 55%, and 16% of other glycosides), a commercial rebaudioside A (containing 98.2% reb A) and material obtained according to EXAMPLE 5.

[0057] The sensory properties were evaluated by 20 panelists. The best results were obtained in samples containing the composition obtained according to EXAMPLE 5. The panelists noted a rounded and complete flavor profile and mouthfeel.

EXAMPLE 10

Yoghurt

[0058] Different Stevia compositions (0.03%) and sucrose (4%) were dissolved in low fat milk. The Stevia compositions were selected from a commercial Stevia extract (containing stevioside 26%, rebaudioside A 55%, and 16% of other glycosides), a commercial rebaudioside A (containing 98.2% reb A) and the material obtained according to EXAMPLE 5. After pasteurizing at 82° C. for 20 minutes, the milk was cooled to 37° C. A starter culture (3%) was added and the mixture was incubated at 37° C. for 6 hours then at 5° C. for 12 hours.

[0059] The sensory properties were evaluated by 20 panelists. The best results were obtained in samples containing the composition obtained according to EXAMPLE 5. The panelists noted a rounded and complete flavor profile and mouthfeel.

[0060] It is to be understood that the foregoing descriptions and specific embodiments shown herein are merely illustrative of the best mode of the invention and the principles thereof, and that modifications and additions may be easily made by those skilled in the art without departing for the spirit and scope of the invention, which is therefore understood to be limited only by the scope of the appended claims.