Fractionation of vanilla oleoresin by supercritical CO2 technology

Abstract

In this work it was determined experimentally the vanilla oleoresin solubility in supercritical CO2 at moderated pressures and it was also studied the vanilla CO2 extraction/fractionation process. The initial equilibrium concentration of vanilla oleoresin in the CO2 extract phase was determined by a dynamic method at 140 bar and 180 bar in a range of temperature of 310.5 K to 348.3 K. A significant change in vanilla oleoresin solubility (2 to 10 g oleoresin/kg CO2) and selectivity towards the extraction of vanillin (main flavor component) was observed according to the operating temperature and pressure. It was also analyzed the CO2 batch fractionation of vanilla oleoresin under equilibrium conditions at 310.5 K and 140 bar in order to obtain a complete vanillin recovery. It was determined a decrease of the vanillin concentration in the extract phase along the fractionation process. A complete vanillin recovery was obtained using a solvent mass ratio of 25 g CO2 / g oleoresin processed.