罗非鱼肉分离蛋白的营养成分分析

以罗非鱼鱼肉为原料,采用pH值调节法(pH-shifting),制备鱼分离蛋白,主要探讨提取条件和沉淀条件对提取蛋白得率及其应用特性的影响.结果表明:在极端酸性(pH<3)和极端碱性(pH>10)条件下,鱼肉蛋白的溶解性较好,而在pH值5-6时溶解性较差,由此选择pH值2、3、11和12条件下溶解,pH值5.5条件下沉...

Analysis of Nutritional Components of Protein Isolates from Tilapia Muscle

Fish protein isolates was prepared from Tilapia muscles by pH-shifting in this study.Effect of extraction and precipitation conditions on protein yield and application features of protein isolates was determined.The results showed that the solubility was better at extreme acidic condition(pH<3) and alkaline condition(pH>10),but the solubility was very poor at pH 5.5.Consequently,protein was extracted at pH 2,3,12 and 13,and then was precipitated at pH 5.5.Under this conditions,the protein yield was 56.06%~64.95%.Protein isolates powder was obtained by freeze-drying,with the crude protein content in dry basis,fat content and ash content being more than 95%,1% and < 2.03%,respectively.And the total essential amino acids were about 49 percent of total amino acids.According to AAS,protein isolates completely accords with adult amino acids demand.For baby level mode,the first and the second restrictive amino acids were tryptophan and lysine,respectively.And high histidine score was found for the protein isolates.All results showed these fish protein isolates could be used as protein food additive.