A new approach to prepare omega -3 and omega -6 fatty acid rich glycerides from vegetable oils for value added food products.

摘要

Triglycerides rich in omega -3 alpha -linolenic and omega -6 linoleic acids were isolated using silver nitrate (A), silver nitrate to zinc sulphate in 1:1 wt/wt ratio (B), and zinc sulphate (C) 15% each with respect to silica gel enrichment columns. Linseed, soybean and wheat germ oils were fractionated on column A, B and C separately using petroleum ether (60-80 degrees C), petroleum ether:diethyl ether (1:1 v/v) and pure diethyl ether to yield I, II and III fractions, respectively. In the case of linseed oil, linoleic and alpha -linolenic acids enriched fraction increased significantly (p<0.05) from 17.1 to 47.2 and 52.2 to 90.3% from column A; 17.1 to 56.5 and 52.2 to 89.3% from column B; 17.1 to 20.2 and 52.2 to 67.1% from column C, respectively. Similar significant (p<0.05) enrichment trends were noticed for soybean and wheat germ oils also. Iodine value supported the data trend obtained by gas liquid chromatograms with respect to extent of unsaturation of these fractions. It has been demonstrated that silver nitrate (a highly expensive chemical) could be replaced by zinc sulphate without compromising the efficacy of enrichment columns. The efficacy of column (C) was almost equal to that of column (A).