Enhancement of the supercritical fluid extraction of grape seed oil by using enzymatically pre-treated seed

摘要

The supercritical fluid extraction of grape seed (Vitis vinifera L) oil using carbon dioxide has been carried out at constant temperature (313.15 K) and solvent flow rate (1.7 x 10~(-4) kg s~(-1)), at 160,180 and 200 bar, using both untreated and enzymatically pre-treated seeds. The pre-treatment of triturated seeds has been performed with a cell wall degrading enzyme cocktail containing cellulase, protease, xylanase, and pectinase, in order to enlarge the broken/intact cells ratio, thus increasing oil availability. The maximum extraction yield obtained was 16.5%, which is 44% higher than the 11.5% yield obtained with untreated seeds. The cumulative extraction curves measured show two characteristic periods: a first linear part where the majority of the oil is obtained, and a second asymptotic branch which contributes with only 3-8% to the total oil removed. As pressure rises, the mass of CO2 needed to reach a definite extraction yield decreases and the linear part of the extraction curves of treated and untreated seed approach themselves.