为获知二段（或分步）酶解工艺对罗非鱼排水解液中风味物质的影响，通过响应面分析法研究了风味蛋白酶二段酶解罗非鱼排的最佳工艺，并分析比较一段酶解液以及二段酶解液中的游离氨基酸种类及含量，同时采用顶空-固相微萃取（ HS-SPME）结合气质联用（ GC-MS）技术对酶解液挥发性风味物质组成进行分析研究。结果显示：在温度为55℃， pH为7.0，加酶量为1315 U/g时，水解4 h，水解度可达47.22％，显著高于一段酶解液（33.70％）；二段酶解液的游离氨基酸总量及必需氨基酸含量分别提高224.39 mg/100 mL和114.15 mg/100 mL，呈鲜味及甜味的氨基酸所占比例提高3.26％；二段酶解液挥发性风味成分中醛类物质的相对含量提高了9.0％，愈创木酚、1-辛烯-3-醇等特征风味物质相对含量有所降低。研究表明，二段酶解工艺不仅可以提高罗非鱼排水解度，还可改善酶解液的风味成分。%In order to learn the effect of two-step enzymatic hydrolysis on the flavor compounds of Tilapia frame hydroly-sates, the optimal conditions of the two-step enzymatic hydrolysis were obtained by using Response Surface Analysis , and then the free amino acids and the volatile flavor components in one-step and two-step hydrolysates were analyzed .Results indicated that the optimal conditions for two-step hydrolysis by flavourzyme were as follows: pH value was 7.0 , time was 4 h, temperature was 55℃, enzyme dosage was 1315 U/g.The degree of hydrolysis could reach 47.22%, 13.52%high-er than that of one-step enzymatic hydrolysis under the optimum values .Total free amino acids and essential amino acids content combined with the proportion of delicious amino acid ( sweet or umami ) in the two-step hydrolysates increased by 224.39 mg/100 mL, 114.15 mg/100 mL and 3.26%, respectively.Meanwhile, the relative ratio of aldehydes in the volatile flavor components from the two-step hydrolysates increased 9.0%.However, the contents of some characteristic flavor compounds such as guaiacol and 1-octene-3-alcohol were significantly reduced .Therefore, two-step enzymatic hy-drolysis methodology could not only improve the degree of hydrolysis , but also improve the flavor compounds of hydroly-sates.
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