Comparison of microbial community and metabolites in spontaneous fermentation of two types Daqu starter for traditional Chinese vinegar production
Comparison of microbial community and metabolites in spontaneous fermentation of two types Daqu starter for traditional Chinese vinegar production
复制标题
两种制醋大曲发酵剂自然发酵过程中微生物群落及代谢产物比较
DOI：
10.1016/j.jbiosc.2019.03.011
复制
发表时间：
2019-09-01
影响因子：
2.8
通讯作者：
Luo, Lixin
中科院分区：
文献类型：
--
作者：
Tang, Hanlan;Liang, Hebin;Luo, Lixin
大曲曲是传统食醋酿造过程中重要的糖化发酵剂，采用中低温自然固态发酵工艺生产。以往的研究表明，温度对大曲品质起着关键作用。为此，为探索高温发酵在食醋大曲酿造中应用的可行性，为传统食醋行业环境参数控制提供指导，对中温和高温发酵过程中食醋大曲的微生物群落和代谢产物(MTFP和HTFP)进行了比较。结果表明，两批次结束时糖化淀粉酶活性、淀粉酶活性和微生物群落均无显著差异(P>；0.05)。肠杆菌属、乳杆菌属、芽孢杆菌属、酵母菌属和毛霉目是MTFP和HTFP中的优势目。冗余度分析表明，培养温度与发酵过程第3-14天的微生物组成呈正相关，与芽孢杆菌、毛霉、黄单胞菌和立克次体的优势系统型呈正相关。酸度和水分与MTFP第1天的微生物组成呈显著正相关，与毛霉目和乳杆菌目的优势系统型呈正相关。此外，HTFP末端所有挥发性物质的相对含量(13.91 mg/100g大曲)高于MTFP(10.01 mg/100g大曲)。这项工作表明，高温(约60℃)发酵有望改善食醋大曲的风味，并可能有助于通过调节可控的环境参数来更好地制作传统大曲。(C)2019年，日本生物技术学会。版权所有。
Daqu starter, an important saccharifying and fermenting agent for the brewing process of traditional vinegar, is manufactured by spontaneous solid-state fermentation which routinely undergoes low or medium incubation temperature. Previous studies have demonstrated that the temperature plays a pivotal role in Daqu quality. Hence, to explore the feasibility of high temperature fermentation applied in the vinegar Daqu brewing and provide guidelines of controlling environmental parameters in traditional vinegar industries, the microbial community and metabolites of vinegar Daqu during medium-temperature and high-temperature fermentation processes (namely, MTFP and HTFP) were compared. The results indicated that the glucoamylase activity, amylase activity and microbial community showed no significant difference in the end of two batches (P > 0.05). Enterobacteriales, Lactobacillales, Bacillales, Saccharomycetales and Mucorales were the dominant orders during MTFP and HTFP. Redundancy analysis revealed that incubation temperature showed positive correlation with the microbial composition from days 3-14 of the fermentation process and was positively associated with the predominant phylotypes of Bacillales, Mucorales, Xanthomonadales and Rickettsiales. The acidity and moisture showed major correlations with microbial composition on day 1 of MTFP and were positively related with the predominant phylotypes of Mucorales and Lactobacillales at the order level. Moreover, higher relative contents of all volatiles were shown in the end of HTFP (13.91 mg/100 g Daqu) compared to MTFP (10.01 mg/100 g Daqu). This work illustrates high temperature (approximately 60 degrees C) fermentation is promising to improve the vinegar Daqu flavor and shall likely contribute to preferably make traditional Daqu by modulating steerable environmental parameters. (C) 2019, The Society for Biotechnology, Japan. All rights reserved.