Wang Xueshan, Du Hai, Xu Yan
State Key Laboratory of Food Science and Technology, The Key Laboratory of Industrial Biotechnology of Ministry of Education, Synergetic Innovation Center of Food Safety and Nutrition, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, People's Republic of China.
State Key Laboratory of Food Science and Technology, The Key Laboratory of Industrial Biotechnology of Ministry of Education, Synergetic Innovation Center of Food Safety and Nutrition, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, People's Republic of China.
Int J Food Microbiol. 2017 Mar 6;244:27-35. doi: 10.1016/j.ijfoodmicro.2016.12.018. Epub 2017 Jan 2.
The fermentation process of Chinese strong-flavor liquor involves numerous microbes originating from Daqu and pit mud. Daqu is the starter of fermentation, and pit mud acts as another source of inoculum of microbes in the liquor-making process. However, the contribution of microbes in pit mud and Daqu to fermented grain, and the sources of microbes in fermented grain are still waiting to be defined clearly. In this study, prokaryotic communities in fermented grain, pit mud and Daqu were identified via next generation sequencing of the V4 region of 16S rRNA gene. Principal-coordinate analysis indicated that Daqu had stronger influence on the prokaryotic communities in fermented grain at the prophase of fermentation, but pit mud influenced the fermented grain continuously during the whole fermentation process. Totally, 299 genera were detected in all fermented grain, pit mud and Daqu samples. Among them, 204 genera were detected in 3days' fermented grain. Ten genera (Lactobacillus, Leuconostoc, Staphylococcus, Gluconobacter, Acetobacter, Petrimonas, Clostridium, Ruminococcus, Methanobacterium and Methanobrevibacter) were dominant, and accounted for 84.31%-87.13% relative abundance of the total prokaryotic community in fermented grain. Venn analysis indicated Daqu was the main source of strict aerobes and facultative aerobes, which took up over 74% of prokaryotic communities in fermented grain. Conversely, pit mud was the sustained-release source of anaerobes, which accounted for over 14% of prokaryotic communities in fermented grain. In addition, part of anaerobes originated from both Daqu and pit mud. This study could help track the source of prokaryotic communities in fermented grain, and improve the quality and controllability in liquor production.
中国浓香型白酒的发酵过程涉及众多源自大曲和窖泥的微生物。大曲是发酵的起始剂，而窖泥在酿酒过程中作为微生物的另一个接种源。然而，窖泥和大曲中的微生物对发酵粮醅的贡献以及发酵粮醅中微生物的来源仍有待明确界定。在本研究中，通过对16S rRNA基因V4区域进行下一代测序，鉴定了发酵粮醅、窖泥和大曲中的原核生物群落。主坐标分析表明，大曲在发酵前期对发酵粮醅中的原核生物群落影响更强，但窖泥在整个发酵过程中持续影响发酵粮醅。在所有发酵粮醅、窖泥和大曲样品中总共检测到299个属。其中，在发酵3天的粮醅中检测到204个属。十个属（乳酸杆菌属、明串珠菌属、葡萄球菌属、葡糖杆菌属、醋酸杆菌属、Petrimonas、梭菌属、瘤胃球菌属、甲烷杆菌属和甲烷短杆菌属）占主导地位，占发酵粮醅中原核生物群落总相对丰度的84.31%-87.13%。Venn分析表明大曲是严格需氧菌和兼性需氧菌的主要来源，它们在发酵粮醅的原核生物群落中占比超过74%。相反，窖泥是厌氧菌的缓释源，在发酵粮醅的原核生物群落中占比超过14%。此外，部分厌氧菌同时来源于大曲和窖泥。本研究有助于追踪发酵粮醅中原核生物群落的来源，并提高白酒生产的质量和可控性。
