Solubility of Stevioside and Rebaudioside A in water, ethanol and their binary mixtures

LILIANA CELAYA; EUGENIO KOLB; NICOLAS KOLB KOZLOBSKY

International Journal of Food Studies

ISEKI

Lugar: Vienna; Año: 2016 vol. 2016 p. 158 - 166

2182-1054

In order to investigate the solubility ofStevioside and Rebaudioside A in different solvents (ethanol, water,ethanol:water 30:70 and ethanol:water 70:30), supersaturated solutions of pre-crystalizedsteviol glycosides were maintained at different temperatures (from 5 °C to 50°C) to reach equilibrium. Under these conditions significant differences werefound in the extent of solubility. RebaudiosideA was poorly soluble in ethanol and water, and Stevioside was poorly soluble inwater. Solvent mixtures more effectively promoted solubilisation,and a significant effect of temperature on solubility was observed. The two steviol glycosides showedhigher solubilities and this behavior was promoted by the presence of the othersweetener. The polarity indices of the solvents were determined, and helped to explain theobserved behavior. Several solute-solvent and solute-solute interactionscan occur, along with the incidence of a strong affinity between solvents. Theobtained results are in accordance with technological applications of ethanol,water and their binary mixtures for Stevioside and Rebaudioside A separations.