传统手工黄酒发酵过程中常见游离氨基酸和γ-氨基丁酸的变化研究

Studies on Common Free Amino Acid and γ-Aminobutyric Acid Contents Change in the Fermentation Process of Manual Chinese Rice Wine

本文研究传统手工黄酒发酵过程中常见游离氨基酸、γ-氨基丁酸以及总糖、酒精度和总酸的变化过程。结果表明,传统手工黄酒发酵过程中常见游离氨基酸和γ-氨基丁酸在前发酵和后发酵前期增加缓慢,在后发酵后期增加迅速;总糖在前发酵期间下降明显,后发酵期间先上升后缓慢下降;酒精度和总酸在前发酵结束时已达到发酵终点的一半左右,随后均缓慢上升。随着后发酵时间的延长,总糖不断下降,酒精度和总酸不断增加,发酵醪中的酵母不断发生自溶,导致常见游离氨基酸和γ-氨基丁酸含量迅速增加。后发酵结束时,发酵醪中GABA 120.555 mg/L,游离必需氨基酸2 825.656 mg/L,游离总氨基酸7 397.065 mg/L,总糖(葡萄糖计)6.757g/L,酒精度18.417%,总酸(乳酸计)6.16 g/L。

The aim of the present work was to obtain the changing of free amino acids and γ-aminobutyric acid （GABA） in the process of the Chinese rice wine fermentation, total sugar, alcohol, and total acid were also investigated. The results showed that free amino acids and GABA increased slowly at primary fermentation and in the early period of the post-fermentation, increased rapidly in the later period of the post-fermentation of the manual Chinese rice wine. Total sugar decreased significantly at primary fermentation; At the end of the primary fermentation, alcohol and total acid have reached the half at the end of fermentation. With the decreasing of total sugar and increasing of total acid and alcohol, the yeast autolyzed constantly, so as to make the contents of common free amino acids and GABA increased rapidly. At the end of the fermentation, content of GABA was 120.555 mg/L, the free essential amino acids 2 825.656 mg/L, total free amino acids 7 397.065 mg/L, total sugar 6.757 g/L, alcohol 18.417%, and total acid 6.16 g/L.