蛋白酶解对鲣鱼肉乳化特性的改善

天然鱼蛋白乳化性不佳,难以满足实际生产需求,但鱼蛋白的酶解改性可改善其功能特性,并拓展应用范围。以鲣鱼白色肉为原料,以水解度和乳化性为主要指标,比较了不同蛋白酶(胰蛋白酶、风味蛋白酶、木瓜蛋白酶)和水解时间对酶解液制备和鱼蛋白乳化性的影响,优化了酶解工艺参数。将鱼蛋白进行冷冻干燥后,分析鱼蛋白酶解前后溶解性、乳化性和起泡性等功能特性的差异。结果表明,当胰蛋白酶添加量2 000 U·g^-1,酶解10 min时,鱼蛋白水解度(DH)达到8.2%,此时鱼蛋白乳化特性最佳。与酶解前样品相比,酶解后鱼蛋白的乳化活性和乳化稳定性显著提高,其溶解度、起泡性和起泡稳定性均有一定程度的改善。酶解制备的鲣鱼蛋白在广泛pH范围内具有更好的功能性质,在食品工业具有更高的应用价值。

Improvement of emulsifying properties of skipjack tuna protein by enzymatic hydrolysis

Owing to the poor emulsifying properties, natural fish protein could not meet the needs of actual production. The protein could be modified by enzymatic hydrolysis to improve its emulsifying properties, meet production needs and broaden its application range. Effects of different enzymes (trypsin, flavourzyme and papain) and hydrolysis time on the preparation of protein hydrolysate and emulsifying properties of fish protein were compared to optimize the process parameters of enzymatic hydrolysis. After freeze-drying of the enzymatic hydrolysate, the differences in functional properties such as solubility, emulsification and foaming properties of fish protein before and after enzymatic hydrolysis were analyzed. The results showed that when the amount of trypsin was 2 000 U·g^-1, hydrolyzed for 10 min, the degree of hydrolysis (DH) of fish protein reached 8.2%, the emulsifying properties of modified fish protein were the best. Compared with the sample before enzymolysis, the emulsification activity and emulsification stability of modified fish protein after enzymatic hydrolysis were significantly improved, and its solubility, foamability and foam stability were improved to a certain extent. The skipjack tuna protein hydrolysate having better functional properties in a broad pH range will had braod application in food industry.