New Zealand fish oils

Abstract

Analyses of 7 samples of ling liver oil showed no significant variation in fatty acid composition, which resembled the avg. marine type with an increased proportion of C 18 unsaturated acids. At least 96.5% of this fraction consisted of octadecenoic acid, together with traces of octadeca-tetraenoic and octadecatrienoic acids. Concordant results were obtained by different methods. Linoleic and linolenic acids were not found. The proportions of component fatty acids in the roe glycerides were similar to those in the liver fat, with more hexadecenoic and less C20 and C22 polyethylenic acids than the corresponding phosphatide fractions. Contrary to the hypothesis of selective molecular filtration, the viscera and roe, which in the ling are minor fat depots as compared with the liver, contained a higher proportion of C20 and C22 unsaturated fatty acids than the liver oil.