山西老陈醋酿造过程中香气成分的动态变化

The Dynamics Changes of Aroma Components in Brewing Process of Shanxi Mature Vinegar

采用GC-MS法研究山西老陈醋发酵过程中香气成分的动态变化,结果表明:酒精发酵阶段,醇类和酯类物质相对含量随发酵时间的延长而增加,分别由发酵起始阶段(0 d)的23.21%和37.18%上升至末期(14 d)的33.55%和56.53%;酸类含量低且无明显变化。进入醋酸发酵阶段,酯类物质含量继续上升,最终达到60.41%;醇类物质因发生酯化反应而呈下降趋势,最终降至8.29%;醋酸菌、乳酸菌等产酸菌代谢活跃,使挥发性酸类物质含量大大提高,从醋酸发酵第0天的1.21%上升至第11天的16.66%。熏醅阶段的挥发作用使得酸类、醇类和酯类化合物的含量逐渐下降,醛类和酚类物质的含量显著提高;另外,两种杂环类化合物——糠醛和四甲基吡嗪的含量上升较快,分别从熏醅第1天的0%和1.04%上升至第5天的20.72%和10.83%。从新淋醋中共检测出18种酯类、5种醇类和3种挥发性酸,相对含量分别为20.08%,7.53%和28.00%,其中对醋风味有重要贡献的为苯乙醇、2,3-丁二醇、乙酸、乙酸乙酯、乙酸苯乙酯和糠醛。

The dynamics changes of aroma components were determined by GC-MS during the whole fermentation process of Shanxi mature vinegar. In alcoholic fermentation, the alcohols and esters exhibit a rising tendency, increased from 23.21%, 37.18%(0 d) to 33.55% and 56.53%(14 d) respectively. The acids maintained a low level along this fermentation period. In acetic acid fermentation stage, the esters continued keeping rising,and finally reached 60.41%. The alcohols began to decline for esterification, and ultimately fell down to 8.29%. The vigorous metabolic activity of acetic acid bacteria and lactic acid bacteria made the relative content of volatile acids greatly increased from 1.21%(0 d) to 16.66%(11 d). During smoking solid-substrate, the contents of acids, alcohols and esters decreased because of water evaporation. However, the aldehydes and phenols increased significantly during this stage. Also, it was noted that two kind of heterocyclic compounds, furfural and tetramethyl pyrazine significantly increased from 0%, 1.04%(0 d) to 20.72% and10.83%(5 d) respectively. At last, total of 18 esters, 5 alcohols and 3 volatile acid were detected in newly leaching vinegar, and the relative contents were 20.08%, 7.53% and 28.00% respectively. Among of which, benzene ethanol, 2,3-butanediol, acetic acid, acetoacetate, phenylethyl acetateacetic acid and furfural were taken as the most important contributors to vinegar flavor.