Study on extraction of fish oil from wastes of fish surimi

Fish oil was extracted from the wastes of fish surimi by the potassium hydroxide hydrolysis. The results show that the process parameters of extraction of fish oil were as follows：hydrolysis temperature 70℃, hydrolysis pH 7.5, hydrolysis time 55 min, the amount of potassium nitrate 4.5%, the saltout time 30 min. Under these conditions, the extraction rate of fish oil was up to 64.5%.The physics and chemistry indexes accorded with the second crude fish oil demand for SC/T3502-2000 standard. The content of the saturated fatty acid was relatively high in fish oil, which accounted for 48.59% of the total amount. The content of monounsaturated fatty acid was equivalent to the content of the polyunsaturated fatty acid, 24.48% and 24.49%, respectively. The polyunsaturated fatty acids were mainly DHA and EPA, the content 11.18% and 5.17%, respectively.