Extraction Methods and Storage Properties of Fish Oil from Viscera of Grass carp (Ctenopharyngodon idellus)

Fish Oil was extracted from viscera of grass carp (Ctenopharyngodon idellus) with diluted alkaline hydrolysis extraction, oil extraction under vacuum, organic solvent extraction and aqueous enzymatic extraction. Effects of temperature (4, 10, 25, 35℃), antioxidants (TBHQ, BHT, VE) and packaging conditions (vacuum packaging, nitrogen-filled packaging) on the quality of fish oil during storage were evaluated by sensory evaluation (odor, color, viscosity, transparency) and physical and chemical indicators (peroxide value, acid value) two aspects. The results indicated that the optimal quality of fish oil was obtained by aqueous enzymatic extraction. And the optimum conditions were:pH8.0, 50℃, 3 h, enzyme dosage 2500 U/g, the ratio of material to water 1:1.And under this conditions, except acid value, other indicators of the fish oil all reached the secondary standard for refined fish oil in SC-T 3502-2016.Furthermore, it was found that low temperature at 4℃, vacuum packaging, and addition of 0.02% TBHQ could alleviate the oxidative deterioration rate of fish oil and improve the storage stability of oil.