Choi Yeung Joon, Hur Sungik, Choi Byeong-Dae, Konno Kunihiko, Park Jae W
Inst. of Marine Industry, Gyeongsang Natl. Univ., Inpyeong-dong, Tongyeong, Korea.
J Food Sci. 2009 Jan-Feb;74(1):C17-24. doi: 10.1111/j.1750-3841.2008.00988.x.
Fish protein isolate were recovered from frozen small croaker using pH shift. The partial enzymatic hydrolysates were fractionated as soluble and insoluble parts. They were dried using the drum dryer and their functional properties were examined. The total nitrogen content of the enzymatic hydrolysates ranged from 12.9% to 13.7%. The degree of hydrolysis of precipitates was 18.2% and 12.2% for croaker hydrolysates treated with Protamex 1.5 MG (Bacilllus protease complex) and Flavourzyme 500 MG (endoproteases and exoproteases, Aspergillus oryzae), respectively. The TCA supernatant, after centrifugation of hydrolysates, contained numerous peptides ranging from 100 to 4000 daltons. The solubility of the supernatants was higher than that of the precipitates at 0% to 3% NaCl and pH 2 to 10. The precipitate of Flavourzyme- and Protamex-treated hydrolysates showed a high emulsion activity index value compared to egg white and bovine plasma protein. In addition, the highest emulsion stability was observed for Protamex-treated precipitate hydrolysates. Emulsion stability of Protamex-treated precipitate hydrolysates was comparable to those of protein additives (egg white, bovine plasma protein, and soy protein concentrate). Water and fat binding capacity of precipitates were higher than those of supernatant. The results indicate that precipitate hydrolysate from undersized croaker can be used in processed muscle foods as a functional and nutritional ingredient.
采用pH值调节法从冷冻小黄花鱼中提取分离鱼蛋白。将部分酶解产物分离为可溶部分和不溶部分。使用滚筒干燥机对它们进行干燥，并检测其功能特性。酶解产物的总氮含量在12.9%至13.7%之间。用Protamex 1.5 MG（芽孢杆菌蛋白酶复合物）和风味酶500 MG（内切蛋白酶和外切蛋白酶，米曲霉）处理的小黄花鱼水解产物沉淀的水解度分别为18.2%和12.2%。水解产物离心后的三氯乙酸上清液中含有许多分子量在100至4000道尔顿之间的肽。在0%至3%的氯化钠和pH值2至10的条件下，上清液的溶解度高于沉淀。与蛋清和牛血浆蛋白相比，经风味酶和Protamex处理的水解产物沉淀显示出较高的乳化活性指数值。此外，经Protamex处理的沉淀水解产物的乳化稳定性最高。经Protamex处理的沉淀水解产物的乳化稳定性与蛋白质添加剂（蛋清、牛血浆蛋白和大豆浓缩蛋白）相当。沉淀的水结合能力和脂肪结合能力高于上清液。结果表明，小规格小黄花鱼的沉淀水解产物可作为功能性和营养性成分用于加工肉类食品。
