Production and characterization of crude oils from seafood processing by-products

The potential use of fish by-products from different species (farmed bluefin tuna, farmed seabass and seabream, and wild sardines) for oil production was investigated. The yield, physicochemical quality, fatty acid profile and nutritive value of tuna by-product and liver oil, wild sardine and sardine by-product oil, and a combined farmed seabass and seabream by-product oil were determined and compared to commercial cod liver oil. In terms of oxidative stability, tuna, seabass and seabream by-product oils had the lowest free fatty acid content, peroxide, Totox, and anisidine value. The oxidative stability of the oils was good and the highest a-tocopherol content in the range of 70.9-79.4 mu g/g was found in seabass and seabream by-products oils. The sum of eicosapentaenoic and docosahexaenoic fatty acids ranged from 11.6 in seabass and seabream oil to 32.8% in sardine oil. The n-3/n-6 ratio of the oils showed value ranging from 0.66 in seabass and seabream by-product oil to 11.0 in sardine oil showing a potential use of fish by-products in high quality oil production, adding economic value to the by-products and changing by-product disposal strategies.