EXTRACTION OF OIL AND MINOR LIPIDS FROM COLD-PRESS RAPESEED CAKE WITH SUPERCRITICAL CO2

This study examines the extraction of oil from cold-press rapeseed cake using Supercritical CO2 (SC-CO2). The effects of pressure (20, 30, and 40 MPa), temperature (40, 50, and 60 degrees C), and extraction time (60, 90, and 120 min) on oil yield and composition (tocopherols and carotenoids) were studied using response surface design. The results indicated that pressure influenced the most the yield of oil, followed by temperature and extraction time. Extraction time had no effect on oil composition. Extraction pressure and temperature did not affect the tocopherol concentration of the oil to a great extent, whereas temperature had no affect in its carotenoid concentration. A comparison was made between the relative qualities of oil extracted with SC-CO2 at 40 MPa and 60 degrees C and with n-hexane. Neither solvent affected the unsaponifiable matter content or the composition of phytosterols (mainly beta-sitosterol, campesterol and brassicasterol) of the oils, although there was a significant difference (p<0.05) in tocopherol. Extraction with SC-CO2 at 40 MPa and 60 degrees C is recommended to obtain rapeseed-oil enriched with tocopherols and carotenoids as important functional components.