Patent

1. A process for producing a stevia food ingredient composition comprising rebaudioside B, comprising the steps of:

providing a stevia sweetener;

providing a biocatalyst capable of hydrolyzing β-glucosyl ester bonds in the stevia sweetener;

dissolving the stevia sweetener and adding the biocatalyst to make a reaction mixture;

incubating the reaction mixture at a temperature of about 10-150° C. for about 12 to 48 hours to at least partially hydrolyze β-glucosyl ester bonds in the stevia sweetener;

cooling the mixture to about 10-30° C. and adjusting the pH with acid to about pH 3.0-4.0 and incubating the mixture to obtain a precipitate comprising rebaudioside B;

separating the precipitate and washing the precipitate with water; and

drying the washed precipitate to obtain the stevia food ingredient composition.

2. The process of claim 1 further comprising the steps of:

suspending the stevia food ingredient composition in water and incubating at a temperature of about 50-100° C. for about 1-3 hours; and

separating the stevia composition from the water and drying the stevia composition to obtain a purified stevia food ingredient composition comprising rebaudioside B having a purity of greater than about 99%.

3. The process of claim 1 further comprising the steps of:

suspending the stevia food ingredient composition in water to form a suspension;

increasing the temperature of the suspension by a gradient heating method;

holding the suspension at a temperature of about 110-140° C.;

decreasing the temperature of the suspension by a gradient cooling method to obtain a stevia food ingredient composition solution; and

spray drying the stevia food ingredient composition solution to provide a highly soluble stevia composition having a solubility greater than 20% in water at room temperature.

4. The process of claim 1 , further comprising the steps of:

dispersing the stevia food ingredient composition in water to form a mixture;

adding a base into the mixture;

incubating the mixture to facilitate at least partial conversion of a carboxyl group of the rebaudioside B into a carboxylate salt to make a rebaudioside B carboxylate salt; and

separating and drying the stevia food ingredient composition comprising the rebaudioside B carboxylate salt.

5. The process of claim 1 wherein the stevia sweetener comprises rebaudioside A.

6. The process of claim 1 wherein the biocatalyst is selected from the group consisting of free cells, immobilized cells, an enzyme, and an enzyme preparation.

7. The process of claim 1 wherein the biocatalyst comprises an enzyme or an enzyme preparation having an enzyme selected from the group consisting of esterases, lipases, cellulases, hemicellulases, hesperidinases and β-glucosidases.