Isomers of monoethylenic fatty acids in some partially hydrogenated marine oils

An analytical study of the monoethylenic isomers in commercial samples of partially hydrogenated herring, whale and seal oils is presented. The results show that with hydrogenated herring oil there is a slight decline in monoene trans content from 37% in C 16 through to 32% in C 22 . With both whale and seal oils, monoene trans contents were constant at 54% and 59%, respectively, throughout all chain lengths. In general the cis and trans positional isomers from hydrogenated whale and seal oils were more scattered than those from hydrogenated herring oil; however in each oil the major cis isomers of each chainlength were indicative of original cis fatty acid isomers in the raw oils.