Comparison of flaxseed oil characteristics of three Pakistani varieties obtained by supercritical CO2 and two conventional extraction methods

Omega-3 (?-3) fatty acids have gained importance for having health effects. The present work was designed to analyse the differences in three Pakistani flaxseed varieties and the effect of extraction methods on flaxseed oil quality. The oil was extracted using green solvent i.e. supercritical CO2 (SC-CO2) and compared with traditional methods namely Soxhlet extraction and mechanical extraction. The oils were significantly different in terms of free fatty acids, iodine values, and peroxide values, while oils were insignificantly different in terms of specific gravity, saponification values, ?-anisidine values, and tocopherol contents. GC-FID results showed that ?-linolenic acid (?-3) was the major fatty acid in oil, ranging from 52.09 to 58.06%. The variation in the different parameters of oils observed in the present work might be correlated with the principle of each type of oil extraction method. Supercritical fluid extraction of flaxseed oil should be employed as it yields superior quality oil by extracting tocopherols and protecting the polyunsaturated oil from oxidation