Seasonal variations in lipids and fatty acid compositions of frigate mackerel Auxis rochei

The seasonal variations in lipids and fatty acid compositions of frigate ma ckerel Auxis rochei caught off Kochi Prefecture were examined from the view point of the effective utilization of fish wastes. The lipid contents varied from 5.2 to 11.6% for the head, which accounted f or about 42% of fish wastes, and from 7.0 to 17.9% for the orbital tissue t hroughout the year. Docosahexaenoic acid (DHA) was the major unsaturated fa tty acid and accounted for more than 22.7% and 24.5% of the total fatty aci ds in the lipids of the head and orbital tissue, respectively. This result indicated that head portion including the orbital tissue may be useful sour ce of DHA production.