洞酿酱香酒第四轮次酒酷发酵过程中微生物群落与挥发性代谢物分析

Analysis of microbial community and volatile metabolites during the fourth round fermented grains fermentation of Dongniang sauce-flavor Baijiu

该研究应用高通量测序技术解析洞酿酱香型白酒第四轮次酒醅发酵过程中微生物菌群多样性,采用顶空固相微萃取(HSSPME)结合气相色谱-质谱联用(GC-MS)技术测定酒醅挥发性代谢物的变化,并揭示属水平上优势微生物菌群之间和优势微生物与挥发性代谢物之间的相关性。结果表明,洞酿酱香型白酒第四轮次酒醅发酵过程中共有11个优势真菌属,包括嗜热真菌属(Thermomyces)、毕赤酵母属(Pichia)、曲霉属(Aspergillus)等;7个优势细菌属,包括枝芽孢菌属(Virgibacillus)、海洋芽孢杆菌属(Oceanobacillus)、乳杆菌属(Lactobacillus)等。优势菌属间共有81对呈正相关,72对呈负相关。酒醅发酵过程中共检测出55种挥发性代谢产物,且以酯类和醇类为主。真菌属中嗜热子囊菌属(Thermoascus)、复膜孢酵母属(Saccharomycopsis)与多种酯类呈正相关;细菌属中高温放线菌属(Thermoactinomyces)、乳杆菌属、克罗彭斯特菌属(Kroppenstedtia)均与近20种挥发性代谢物具有相关性。

In this study,the diversity of microbial flora was analyzed during the fourth round fermented grains of Dongniang sauce-flavor(Jiangxiangxing)Baijiu brewing by high-throughput sequencing technology,the changes of volatile metabolites in fermented grains were determined by headspace solid phase microextraction-gas chromatography-mass spectrometry(HS-SPME-GC-MS),and the correlation between dominant microorganism genera and volatile metabolites was analyzed.The results showed that there were 11 dominant fungi genera during the fourth round fermented grains of Dongniang sauce-flavor Baijiu brewing,including Thermomyces,Pichia,Aspergillus and so on.There were 7 dominant bacteria genera,including Virgibacillus,Oceanobacillus,Lactobacillus and so on.A total of 81 pairs of dominant bacteria genera were positively correlated,and 72 pairs were negatively correlated.A total of 55 volatile metabolites were detected in fermented grains during fermentation process,mainly esters and alcohols.Among the fungi genera,Thermoascus and Saccharomyces were positively correlated with various esters,and Thermoactinomycetes,Lactobacillus and Kroppenstedtia were all associated with nearly 20 volatile metabolites in the bacterial genus.