Principal Fatty Acids of Depot Fat and Milk Lipids from Harp Seal (Pagophilus groenlandica) and Hooded Seal (Cystophora cristata)

Abstract

The fatty acid compositions of six samples of depot fat taken from harp seals (Pagophilus groenlandica), ranging in age from 1 to 2 days to adult, and a sample of milk lipids, were determined by gas–liquid chromatography (GLC). Three depot fat samples taken from hooded seals (Cystophora cristata), a sample of milk lipids from this species, and commercial seal oils from 4 years' production were similarly analyzed.No significant differences could be found between the composition of the milk lipids and the depot fat of the harp seals at the different ages, other than slightly lower iodine values in the younger animals (avg 140.6 vs. 148.9). The lipid samples from hooded seals had low iodine values (107–127) and correspondingly lower concentration of highly unsaturated fatty acids. The ratio of the fatty acids 22:5ω3/22:6ω3 could be used to differentiate between depot fat from harp seals (ratio 0.51–0.74) and that from hooded seals (ratio 0.25–0.42) in the samples analyzed.Commercial oils, which consist essentially of oil from harp seals, were similar in composition to oil prepared from this species alone.No difference could be found in the iodine values or fatty acid compositions of samples taken from various parts of the animal or from samples representing a cross section of blubber.