对鱼油的提取工艺、鱼油的功能性研究和市场开发进行了综述,鱼油中DHA和EPA含量较高,具有很高的营养价值和很好的开发利用前景。以罗非鱼加工下脚料提取鱼油不仅能提高罗非鱼产品的附加值,而且还能促进罗非鱼养殖加工产业良性发展,具有重要的经济价值和现实意义。
Fish oil was extracted from Tilapia byproduct by hydrolysis,regarding the extraction rate of crude fish oil as the experimental indexes.The optimum Alcalase hydrolysis condition was studied by using orthogonal experiment.The results showed the following optimal conditions:collagen was heated directly for 2 h at pH 7.5 and 55℃by added alcalase enzyme 1 750 U/g of collagen(solid to liquid was 1:2).Under these conditions extraction rate offish oil was 12.56%.the sentry evaluation was carried and the physical and chemical indicators are conducted of fish oil extracted.The results show that the crude fish oil with light fishiness was reddish brown and slightly turbid.Water and volatile matter concentration was 0.42%.The acid value of fish oil extracted was 9.29 mg/g,the peroxide value of fish oil was 8.35 mmol/kg.The iodine value was 135.87 g/(100 g).The impurity content was 0.32%.The physics and chemistry indexes achieved to the second crude fish oil in standard specifications of the aquatic products.
The invention discloses a method for extracting crude fish oil in leftovers of tilapia. The method includes the following steps that at first, the leftovers of the processed tilapia are cleaned and minced after gall bladders are cleared out, and put into an enzymatic vessel, and then Alcalase enzyme and trypsinase are added step by step into the enzymatic vessel for enzymolysis; after the enzymolysis, the enzymatic hydrolysate is centrifuged to produce crude fish oil I; the centrifuged emulsion is frozen, thawed, demulsified, and centrifuged for the second time to produce crude fish oil II. The invention decomposes the protein of the tilapia leftovers by protease, releases fat from protein and degrades the protein combining emulsion with fat and produced in the enzymolysis process; the invention is also combined with the freezing, thawing and emulsion breaking technology, improving the crude fish oil extraction rate of tilapia and the added value of the product.
