EXTRACTION OF VICTORIA AND RED GLOBE GRAPE SEED OILS USING SUPERCRITICAL CARBON DIOXIDE WITH AND WITHOUT ETHANOL

Abstract

SFE of the oils of two varieties of grape seeds (Victoria and Red Globe) was performed in a flow apparatus at 40C and 250 bar. The effect of the solvent on the extraction yield was studied using CO2 and CO2 modified with ethanol, and the yield of extraction was compared with conventional extrac- tion methods (Bligh and Dyer and Soxhlet using hexane). SC CO2 + ethanol extracted higher lipid amounts from both varieties, compared with SC CO2 extraction. The comparison between SFE and conventional extraction methods showed that the highest extraction yield was obtained with SC CO2 + ethanol (10%, w/w) (14.7 and 11.8% for Red Globe and Victoria grape seeds, respectively), while pure SC CO2 afforded the lowest lipid yields. The fatty acid compositions of the oils obtained by SFE were analyzed. Fractions containing higher proportions of PUFAs were obtained at lower solvent/dry grape seed ratios, while fractions richer in SFAs and MUFAs were obtained at higher solvent/dry grape seed ratios.