The Studies On Enrichment Of PUFA Of Ictalurus Punctatus

Fish oil is a kind of natural functional food and its availability is high. It contains abundant polyunsaturated fatty acids. Its main active components are PUFA such as EPA and DHA. The extraction of the Ictalurus punctatus visceral fat and skin fish oil were studied. The preparation of Ictalurus punctatus fish oil fatty acids were studied. The enrichment of the visceral fat and skin fish oil PUFA by urea inclusion were also studied. These researches provide theoretical and technology supports for the utilization of Ictalurus punctatus by-products.(1) The study on the extraction technology of Ictalurus punctatus fish oil through enzymatic method:The extraction rates of alkaline protease, trypsin, neutral protease were 72.1% and 78.6%,75.6% and 81.3%,87.4% and 89.8%, neutral protease was suitable for the extraction processing of the Ictalurus punctatus visceral fat and fish skin as the experimental enzyme. Through single-factor experiments and orthogonal combination test, the best process parameters of the enzymatic extraction of the Ictalurus punctatus visceral fat fish oil by neutral protease enzyme was determined:neutrase adding volumes 0.11%, enzymolysis temperature 50℃, enzymolysis time 4h, pH value 7.0, Under this condition, the extraction rate of visceral fat fish oil reached 91.5%; Through single-factor experiments and orthogonal combination test, the best process parameters of the enzymatic extraction of the Ictalurus punctatus skin fish oil by neutral protease enzyme was determined:neutrase adding volumes 0.20%, enzymolysis temperature 55℃, enzymolysis time 5h, pH value 7.0, Under this condition, the extraction rate of visceral fat fish oil reached 12.8%.(2) The study on preparation of Ictalurus punctatus fish oil fatty acids:KOH concentration, reaction temperature, reaction time are the main factor that affect preparation of fish oil fatty acids. Through single-factor experiments and orthogonal combination test, the best process parameters of preparation of Ictalurus punctatus fish oil fatty acids was determined:KOH concentration 0.2mol/L, reaction temperature 80℃, reaction time 140min,Under this condition, fish oil fatty acid value is 190.5.(3)The study on the enrichment technology of Ictalurus punctatus visceral fat and skin fish oil PUFA through urea inclusion method:Through single-factor experiments and orthogonal combination test, the best process parameters of the urea inclusion enrichment of PUFA and EPA DHA from the Ictalurus punctatus visceral fat fish oil was determined: urea/oil 3:1,95% ethanol/urea 4:1, crystallization temperature-10℃, crystallization time 25h, percentage content of PUFA is 90.12%, percentage content of EPA and DHA is 9.16%; Through single-factor experiments and orthogonal combination test, the best process parameters of the urea inclusion enrichment of PUFA and EPA DHA from the Ictalurus punctatus skin fish oil was determined:urea/oil 3:1,95% ethanol/urea 5:1, crystallization temperature -10℃, crystallization time 25h, percentage content of PUFA is 88.56%, percentage content of EPA and DHA is 9.14%.