Quality of Canola Oil Obtained by Conventional and Supercritical Fluid Extraction

Abstract

Quality of canola oil obtained by the supercritical\rfluid extraction (SFE), using CO2 with ethanol as a co-solvent, was\revaluated and compared to that of the conventionally-obtained oils using either n-hexane or chloroform methanol mixture. Physical\rcharacteristics, chemical properties, fatty acid composition and phenolic\rprofile of oils were investigated. The SFE oil showed significantly lower\rmelting point, peroxide value (PV) and higher free fatty acids (FFAs) and iodine\rvalue (IV) than the n-hexane-extracted\rone. There were no significant differences in the fatty acid composition of\rdifferent oils. The SFE oil showed significantly higher phenolic content\r(35.91, 10.15, 3.16, 0.32 and47.48mg/g of sinapic acid, sinapine, sinapoyl glucose, canolol and total\rphenolics) as compared to 0.08, 0.70, 0.88, 0.45 and0.71mg/g,\rrespectively in the n-hexane-extracted\roil. These results indicate the superiority of SFE and advocate its use for the\rextraction of highly stable and functional canola oil for further health and\rnutraceutical uses. The present results have an industrial and technological\rrelevance as SFE could be competitive with the traditional extraction\rtechniques providing an environmental approach and enhancing the obtained oil\rquality and stability. After recovery of the initial installation costs, SFE\rcould be more economic than conventional extraction. However, further\reconomical studies are needed to validate this last conclusion.