Liu Pulin, Miao Lihong
College of Biological and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, China.
Front Microbiol. 2020 Jan 31;11:75. doi: 10.3389/fmicb.2020.00075. eCollection 2020.
Baiyunbian baijiu, the most popular miscellaneous-flavor baijiu in China, has been widely consumed for decades. Similar to many Chinese baijiu, Baiyunbian baijiu is fermented in five successive batches every year. Sensory analysis demonstrated that the raw baijiu obtained from the last two fermentation batches always has better quality than that produced from the former three batches. In this study, the microbial compositions of fungi and bacteria in each fermentation batch were investigated via high-throughput sequencing. The results showed that , , and dominated the bacterial community in the last two batches, and the most prevalent fungi were , , and . In contrast, large percentages of fungi belonging to , , , and and prokaryotes belonging to , , and were observed in the former three fermentation batches. GC-MS analysis revealed that the fermented grains sampled from the latter two batches contained high concentrations of ethyl lactate, 2,3-butanediol and ethyl caproate, which were mainly generated by co-fermentation of and yeast. The high acidity of the fermented grains in the fourth and fifth fermentation batches as well as the large contents of ethanol and moisture promoted the formation of the functional microbial community. This study provides insight into factors that influenced the baijiu fermentation and is helpful for developing new fermentation techniques with higher baijiu quality.
白云边白酒是中国最受欢迎的兼香型白酒，几十年来一直被广泛饮用。与许多中国白酒类似，白云边白酒每年分五批连续发酵。感官分析表明，从最后两批发酵得到的原酒质量总是优于前三批生产的原酒。在本研究中，通过高通量测序研究了每批发酵中真菌和细菌的微生物组成。结果表明，在最后两批中， 、 和 主导了细菌群落，最普遍的真菌是 、 和 。相比之下，在前三批发酵中观察到属于 、 、 和 的真菌以及属于 、 和 的原核生物占很大比例。气相色谱-质谱联用（GC-MS）分析表明，从后两批取样的发酵糟醅中含有高浓度的乳酸乙酯、2,3-丁二醇和己酸乙酯，它们主要由 和酵母共同发酵产生。第四批和第五批发酵糟醅的高酸度以及乙醇和水分的大量含量促进了功能性微生物群落的形成。本研究深入了解了影响白酒发酵的因素，有助于开发具有更高白酒品质的新发酵技术。
