红谷黄酒发酵过程中微生物多样性与理化指标、挥发性风味的相关性分析

为探究红谷黄酒发酵过程中微生物群落与理化指标、挥发性风味之间的相关性，本研究通过微生物高通量测序技术、理化指标检测及气相色谱-质谱技术等对黄酒样品进行测定并用SPSS软件进行相关性分析。结果显示随着发酵的进行，还原糖含量在初期急剧下降后逐渐稳定，酒精度变化与之相反；总酸含量先快速增加后减少再增加，pH较为稳定；氨基态氮含量先波动增加后急剧上升，可溶性固形物含量先剧烈下降后趋于稳定。发酵过程中10次取样（1～7、10、20、30 d）共检测出14个细菌门和228个细菌属；7个真菌门和108个真菌属。在属水平细菌群落可聚类为3类，真菌群落可聚类为5类。细菌属水平与总酸显著正相关（P<0.05），与还原糖显著负相关（P<0.05），真菌属水平与氨基态氮显著正相关（P<0.05）。2,3-丁二醇以及乳酸乙酯与大部分菌属显著正相关（P<0.05）。Klebsiella与辛酸乙酯显著负相关（P<0.05）;Lactococcus与乙醇、2-丁醇、异丁醇、苯乙醇和棕榈酸乙酯呈显著负相关（P<0.05）。Monascus与乳酸乙酯显著负相关（P<0.05）;A...

Correlation Analysis between Microbial Diversity and Physicochemical Indexes,Volatile Flavor during the Fermentation of Red Millet Huangjiu

In order to explore the correlation between physicochemical indexes, volatile flavor and microbial diversity during the fermentation of red millet Huangjiu, high throughput sequencing of microorganisms, physicochemical index detection and gas chromatography-mass spectrometry were used and SPSS software was applied for correlation analysis. The results showed that during the progress of fermentation, the content of reducing sugar decreased rapidly at first and then became stabilized gradually, while the trend of alcohol content was opposite; the content of total acid increased rapidly in the early stage, then decreased and finally increased again, while the pH value stayed at a same level; the alteration of amino acid nitrogen level was volatility rised in the beginning and then increased fast, while soluble solids content first declined quickly and then kept stabilized. A total of 14 bacterial phyla and 228 bacterial genera, 7 fungal phyla and 108 fungal genera were detected in 10 stages (1~7, 10, 20, 30 days) during fermentation. At the genus level, the bacterial community could be clustered in 3 types, and the fungal community could be clustered in 5 types. Bacteria genus levels were positively correlated with total acid (P<0.05) while negatively correlated with reducing sugar (P<0.05), and fungi genus levels were positively correlated with amino nitrogen (P<0.05). 2,3-Butanediol and ethyl lactate were positively correlated with most of the bacteria (P<0.05). Klebsiella was negatively correlated with ethyl octanoate (P<0.05), while Lactococcus was negatively correlated with ethanol, 2-butanol, isobutanol, phenylethanol and ethyl palmitate (P<0.05). Monascus was significantly negatively correlated with ethyl lactate (P<0.05), while Apiotrichum was negatively correlated with 2-butanol, isobutanol and isoamyl alcohol (P<0.05). Our results indicated that the microbial diversity significantly changed during the fermentation of red millet Huangjiu, which had a certain correlation with the physicochemical indicators and flavor variations. These findings provided a theoretical reference for the subsequent study on quality improvement and deve-lopment of red millet Huangjiu.