苹果醋发酵过程中L-苯丙氨酸促进乙酸-2-苯乙酯的合成

为了初步研究食品添加剂L-苯丙氨酸对苹果醋发酵过程中的特征性香气成分乙酸-2-苯乙酯的合成途径及关键酶活的影响,采用HS-SPME-GC-MS和ELISA,检测各合成相关基质生成量和关键酶活性的变化。结果表明,不同添加量的L-苯丙氨酸有明显促进乙酸-2-苯乙酯及其相关合成基质生成量积累的作用,并且对ADH、AAT的酶活性也有一定的促进作用,而对Esterase酶活性有抑制作用。其中当L-苯丙氨酸添加量为8 g/L时,乙酸-2-苯乙酯生成量显著提高了43.76%～86.59%。因此,本试验初步将8 g/L作为L-苯丙氨酸的最佳添加量,初步推测L-苯丙氨酸通过醇酰基转移酶途径促进乙酸-2-苯乙酯的合成及其相关基质和关键酶活的生成量,赋予苹果醋产品更多独特的香气和风味,为生产工艺提供一定的参考依据。

L-phenylalanine-induced the Synthetic of Acetic Acid-2-phenyl Ethyl Ester in Apple Vinegar Fermentation

In order to study the effects of L-phenylalanine (a food additive) on the synthetic pathway and key enzyme activity related to acetic acid-2-phenyl ethyl ester in apple vinegar fermentation, HS-SPME-GC-MS and ELISA were employed to detect the changes of the matrix concentration and key enzyme activities in the synthesis of acetic acid-2-phenyl ethyl ester. It was shown that different amounts of L-phenylalanine can significantly promote the production of acetic acid-2-phenyl ethyl ester and the synthesis of the related matrix, and L-phenylalanine can increase the enzymatic activities of ADH and AAT, however, it suppressed the activity of Esterase enzyme. When 8 g/L of L-phenylalanine was added, the concentration of acetic acid-2-phenyl ethyl ester significantly increased from 43.76% to 86.59%;Therefore, the optimum additive amount of L-phenylalanine was 8 g/L, speculating that L-phenylalanine induced the synthesis of acetic acid-2-phenyl ethyl ester and its related matrix, and increased key enzyme activities through alcohol acyltransferase pathway, which increased the unique aroma and flavor of apple vinegar products and provided a reference for the production process.