Patent ID: 8030481

Claim:
A method for purifying a polymorphic and/or amorphous form of stevioside consisting of: combining a crude stevioside mixture containing an extract from Stevia plants and an aqueous organic solvent to form a stevioside solution, the aqueous organic solvent containing water in an amount from about 5% to about 25% by weight and at least one organic solvent; and crystallizing the stevioside solution in a single crystallization step to obtain a polymorphic and/or amorphous stevioside composition containing stevioside in a purity greater than 95% by weight on a dry basis; wherein the crude stevioside mixture contains comprises stevioside in a purity from about 60% to about 85% by weight on a dry basis; and wherein the at least one organic solvent is selected from the group consisting of acetone, acetonitrile, methanol, ethanol, 1-propanol, isopropanol, 1-butanol, 2-butanol, tert-butanol, isobutanol, and mixtures thereof.