HIGHLY SOLUBLE STEVIA SWEETENER

Abstract

A method for making highly soluble Stevia sweetener compositions is described. The resulting sweetener compositions readily provide high concentration solutions, and also possess superior taste qualities. The compositions can be used as sweeteners, sweetness enhancers, and flavor enhancers in foods, beverages, cosmetics and pharmaceuticals.

Claims

1. A method for producing a high solubility Stevia sweetener comprising the steps of: A) providing a first Stevia sweetener comprising Rebaudioside D; B) providing a second Stevia sweetener that is different from the first Stevia sweetener comprising rebaudioside A or rebaudioside B; C) providing water; D) mixing the water and first and second Stevia sweeteners to make a mixture; E) increasing the temperature of the mixture by a gradient method to make a solution; F) holding the solution at an elevated temperature; G) decreasing the temperature of the solution by a gradient method to obtain a high stability and high concentration Stevia sweetener solution; wherein the high solubility and high stability sweetener does not show any crystallization up to 5 minutes incubation at 80° C.

2-3. (canceled)

4. The method of claim 1 wherein a ratio of the first and second Stevia sweeteners is about 99:1 to 1:99.

5-12. (canceled)

13. The method of claim 1 wherein a ratio of water to the combined first and second Stevia sweeteners is about 1:1 to 10:1.

14. The method of claim 1 wherein the water and Stevia sweetener mixture is heated at a gradient of about 1° C. per minute to a temperature of about 118-125° C.

15. The method of claim 1 wherein the water and Stevia sweetener mixture is held at a temperature of about 118-125° C. for a period of about 50-70 minutes.

16. The method of claim 1 wherein the temperature of the solution is cooled down to a temperature of about 80° C. at gradient of about 1° C. per minute to obtain the high stability and high concentration Stevia sweetener solution.

17. The method of claim 1 wherein high stability and high concentration Stevia sweetener solution is spray dried on a spray drying apparatus operating at about 175° C. inlet and about 100° C. outlet temperatures to obtain a high solubility Stevia sweetener powder.

18. The method of claim 1, wherein a pH of high stability and high concentration Stevia sweetener solution is adjusted by alkaline solution to about pH 4.5 to 7.0.

19. A high solubility Stevia sweetener powder made by the process of claim 17.

20. The high solubility Stevia sweetener powder of claim 19, having a solubility of at least about 0.5 grams per 100 grams of water.

21. The high solubility Stevia sweetener powder of claim 19, having a solubility of at least about 1.0 gram per 100 grams of water.

22. The high solubility Stevia sweetener powder of claim 19, having a solubility of at least about 5.0 grams per 100 grams of water.

23. The high solubility Stevia sweetener powder of claim 19, having a solubility of at least about 10.0 grams per 100 grams of water.

24. (canceled)

25. A sweetener composition comprising a high solubility Stevia sweetener powder made by the process of claim 17 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, maltodextrins, corn syrup solids, glucose, maltose, sucrose, lactose, aspartame, saccharin, sucralose, sugar alcohols, and a combination thereof.

26. A flavor composition comprising a high solubility Stevia sweetener made by the process of claim 17 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.

27. A food ingredient comprising a high solubility Stevia sweetener made by the process of claim 17 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, stabilizers, thickeners, gelling agents, and a combination thereof.

28. A food, beverage, cosmetic or pharmaceutical product comprising high solubility Stevia sweetener made by the process of claim 17.

29-30. (canceled)

31. The method of claim 17 wherein a ratio of the first and second Stevia sweetener is about 50:50 to 95:5 (w/w).

32. The method of claim 17 wherein a ratio of the first and second Stevia sweetener is about 70:30 to 90:10 (w/w).

33. The method of claim 17 wherein a ratio of water to the combined first and second Stevia sweeteners is about 3:1 to 6:1 (v/w).

34. The method of claim 17 wherein a pH of high stability and high concentration Stevia sweetener solution is adjusted by alkaline solution to about pH 5.5 to 6.0.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0018] A process for the preparation of highly soluble Stevia sweetener, particularly a Stevia sweetener comprising Reb D, is described herein.

[0019] Crystalline Reb D has an inherently low solubility, ranging from about 0.01%-0.05%. The need exists, therefore, for a process in which a high solubility Reb D or compositions thereof are prepared.

[0020] In one embodiment of the present invention, initial materials, comprising sweet glycoside(s) of the Stevia rebaudiana Bertoni plant extract, which includes Rebaudioside D, Stevioside, Rebaudioside A, Rebaudioside B, Rebaudioside C, Rebaudioside E, Rebaudioside F, Steviolbioside, Dulcoside A, Rubusoside or other glycoside of steviol and combinations thereof were combined with the water at ratio of 1:1 to 1:10, preferably 1:3 to 1:6 (w/v).

[0021] The obtained mixture was further subjected to a gradient heat treatment that resulted in high stability and high concentration solution. The gradient of 1° C. per minute was used in heating the mixture. The mixture was heated to the temperature of 110-140° C., preferably 118-125° C. and was held at maximum temperature for 0-120 min, preferably 50-70 min.

[0022] After the heat treatment the solution was cooled down to about 80° C. at gradient of 1° C. per minute. This high stability and high concentration solution did not show any crystallization during up to 1-hour incubation.

[0023] The solution was spray dried by laboratory spray drier operating at 175° C. inlet and 100° C. outlet temperature. A highly soluble amorphous compositions of Reb D were obtained with >1% solubility in water at room temperature.

[0024] In another embodiment of this invention the initial materials were selected from the group including Reb D, Reb A, Rebaudioside B (Reb B), and steviolbioside (Sbio)

[0025] In yet another embodiment combining the Reb D and Reb B, treating and spray drying it by the methods described above, yields a composition with significantly higher solubility (about 1%) compared to the composition obtained by combination of Reb D and Reb A at the same ratio (about 0.5%). This phenomenon was unexpected, as both Reb D and Reb B have <0.1% solubility, whereas the Reb A used in the experiment had >5% solubility. Therefore combinations of Reb D and Reb A were expected to have higher solubility compared to combinations of Reb D and Reb B.

[0026] In one embodiment the said combination comprises Reb D and Reb B at a ratio from 50%:50% to 80%:20%, preferably 70%:30% to 80%:20%. The resulting product has a solubility ranging from 0.5% to 2%.

[0027] In yet another embodiment the Reb B was fully or partially, converted into carboxylate salt form. The solution containing RebD and Reb B, after heat treatment and subsequent cooling (as described above), was mixed with solution of base to achieve a pH level of 4.5-7.0, preferably pH 5.5-6.5. The obtained mixture was spray dried as described above. Alternatively other reactions able to convert Reb B into carboxylate salt form may be used as well. The preferred cations were K.sup.+ and Na.sup.+, and the bases - KOH and NaOH respectively. However those skilled in art should recognize that other carboxylate salts of Reb B can be prepared in a similar manner.

[0028] In one embodiment the taste properties of compositions comprising Reb D and Reb B were compared with compositions comprising Reb D and Reb A at the same ratio. The evaluation shows that combinations of Reb D and Reb B possessed superior taste properties compared to combinations of Reb D and Reb A. Particularly the compositions of Reb D and Reb B showed almost no lingering and bitterness, and more rounded sugar-like taste profile.

[0029] The obtained compositions can be used as sweetener, sweetness enhancer, and flavor enhancer 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.

[0030] 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.

[0031] The compositions can be used “as-is” or in combination with other sweeteners, flavors and food ingredients.

[0032] 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, maltodextrins, corn syrup solids, glucose, maltose, sucrose, lactose, aspartame, saccharin, sucralose, sugar alcohols.

[0033] Non-limiting examples of flavors include lemon, orange, fruit, banana, grape, pear, pineapple, bitter almond, cola, cinnamon, sugar, cotton candy, vanilla flavors.

[0034] 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, stabilizers, thickeners, gelling agents.

[0035] The following examples illustrate preferred 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 Reb D Concentrated Solution

[0036] 100 g of rebaudioside D produced by PureCircle Sdn Bhd (Malaysia), with 98.1% purity (dry weight basis), having water solubility of 0.03% at room temperature was mixed with 400 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 80° C., at 1° C. per minute to make Solution#1.

Example 2

Preparation of Reb D and Reb A Concentrated Solution

[0037] 70 g of rebaudioside D with 98.1% purity (dry weight basis), having water solubility of 0.03% and 30 g of rebaudioside A with 98.6% purity (dry weight basis), and having water solubility of 5.5%, both produced by PureCircle Sdn Bhd (Malaysia), were mixed with 400 g water and subjected to heat treatment as described in EXAMPLE 1 to make Solution#2.

Example 3

Preparation of Reb D and Reb B Concentrated Solution

[0038] 70 g of rebaudioside D with 98.1% purity (dry weight basis), having water solubility of 0.03% and 30 g of rebaudioside B with 99.0% purity (dry weight basis), and having water solubility of 0.01%, both produced by PureCircle Sdn Bhd (Malaysia), were mixed with 400 g water and subjected to heat treatment as described in EXAMPLE 1 to make Solution#3.

Example 4

Concentrated Solution Stability

[0039] Solution#1, solution#2 and solution#3 prepared according to EXAMPLE 1, EXAMPLE 2 and EXAMPLE 3 were assessed in terms of their stability. The results are summarized in Table 2.

[0039] TABLE-US-00002 Concentrated solution stability (80° C.) Time, min Observation Solution#1 Solution#2 Solution#3 1 Cloudy solution Clear solution Clear solution 5 Intensive crystallization Cloudy solution Clear solution 15 Viscous slurry of crystals Intensive crystallization Clear solution 30 Solidified crystalline mixture Viscous slurry of crystals Clear solution 60 Solidified crystalline mixture Solidified crystalline mixture Cloudy solution

It can be seen that the solution prepared by combining reb D and reb B shows greater stability towards crystallization.

Example 5

Preparation of Highly Soluble Rebaudioside D Compositions

[0040] Freshly prepared solution#1, solution#2 and solution#3 prepared according to EXAMPLE 1, EXAMPLE 2 and EXAMPLE 3 were spray dried using YC-015 laboratory spray drier (Shanghai Pilotech Instrument & Equipment Co. Ltd., China) operating at 175° C. inlet and 100° C. outlet temperature. Solutions were maintained at 80° C. to prevent premature crystallization. The solution#1 yielded sample #1, solution #2 yielded sample #2 and solution #3 yielded sample #3.

[0041] The obtained amorphous powder samples were compared for solubility (Table 3).

TABLE-US-00003 Solubility of Rebaudioside D compositions Solubility, % Observation Sample#1 Sample#2 Sample#3 0.01 Clear solution Clear solution Clear solution 0.05 Slightly cloudy solution Clear solution Clear solution 0.5 Cloudy solution Slightly cloudy solution Clear solution 1.0 Visible undissolved matter Cloudy solution Clear solution 1.5 Visible undissolved matter Visible undissolved matter Slightly cloudy solution

Example 6

Taste Profile of Rebaudioside D Compositions

[0042] Taste profiles of sample#1, sample#2 and sample#3 prepared according to EXAMPLE 5 were compared. A model zero-calorie carbonated beverage according to formula presented below was prepared.

[0042] TABLE-US-00004 Ingredients Quantity, % Cola flavor 0.340 ortho-Phosphoric acid 0.100 Sodium citrate 0.310 Sodium benzoate 0.018 Citric acid 0.018 Sample# 1 or 2 or 3 0.050 Carbonated water to 100

[0043] The sensory properties were evaluated by 20 panelists. The results are summarized in Table 4.

TABLE-US-00005 Evaluation of zero-calorie carbonated beverage samples Taste attribute Number of panelists detected the attribute Sample #1 Sample #2 Sample #3 Bitter taste 0 10 0 Astringent taste 0 12 1 Aftertaste 0 11 1 Comments Quality of sweet taste Clean (20 of 20) Bitter aftertaste (11 of 20) Clean (18 of 20) Overall evaluation Satisfactory (20 of 20) Satisfactory (7 of 20) Satisfactory (17 of 20)

[0044] The above results show that the beverages prepared using the compositions comprising Reb D and Reb B (sample#3) possessed almost similar taste, profile with pure reb D (sample #1), at the same time exceeding pure Reb D in solubility almost 20 times. On the other hand compositions comprising Reb D and Reb A (sample#2) possessed inferior solubility and taste profile compared to sample #3.

Example 7

Preparation of Reb D and Reb B Carboxylate Salt Composition

[0045] 70 g of rebaudioside D with 98.1% purity (dry weight basis), having water solubility of 0.03% and 30 g of rebaudioside B with 99.0% purity (dry weight basis), and having water solubility of 0.01%, both produced by PureCircle Sdn Bhd (Malaysia), were mixed with 400 g water and subjected to heat treatment as described in EXAMPLE 1 to make concentrated solution. The pH of the solution was adjusted with 40% KOH to pH 6.0 and the solution was spray dried as described in EXAMPLE 5. The taste profile of obtained carboxylate salt composition was compared with sample#3 of EXAMPLE 5, according to procedure described in EXAMPLE 6. No significant differences between sample #3 and the carboxylate salt composition were revealed during the comparison.

[0046] The process of the present invention resulted in a Rebaudioside D compositions that demonstrated high degree of solubility in water, and superior taste profile. Although the foregoing embodiments describe the use of Rebaudioside D, Rebaudioside B and Rebaudioside A, it is to be understood that any Stevia-based sweetener may be used and prepared in accordance with this invention, and all Stevia-based sweeteners are contemplated to be within the scope of the present invention.

[0047] Although the invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the application is not intended to be limited to the particular embodiments of the invention described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the invention, the compositions, processes, methods, and steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the invention.