Recovery and Characterization of Fish Oil from By-products of Sardine ( Sardina pilchardus ) in the Canning Process

The objective of this study aimed to recover and characterize fish oil from by-products generated in the sardine fillet canning process. The oil was recovered by hydraulic pressing at 85°C for 30 min. This experiment was done twice a month for one year. The recovery oil samples were analyzed for their fatty acids profile, acidity, peroxide value, and p-anisidine value. The results of this study showed that recovery yield varied significantly during the year depending on the catching period, from 6.0% (April) to 32.9% (July). The average values of acidity, peroxide value, and p-anisidine value were 1.43% oleic acid, 4.61 mEq active oxygen/kg oil, and 4.25, respectively. The fatty acid categories and individual fatty acids of the recovered oil showed a significant seasonal dependency. The sum of polyunsaturated fatty acids ranged from 35.29 to 42.93%. Within this group, the most important acids are eicosapentaenoic acid 20:5 n-3 (EPA) and docosahexaenoic acid 22:6 n-3 (DHA). The EPA and DHA ranges were 20.46–24.95% and 4.57–10.18%, respectively. This study confirmed the ability to recover high quality food-grade oil from by-products of the fish canning industry that can be used in other food products to ameliorate their nutritional quality.