College of Liquor and Food Engineering, Key Laboratory of Fermentation Engineering and Biological Pharmacy of Guizhou Province, Guizhou University, Guiyang, Guizhou 550025, China; Key Laboratory of Fermentation Engineering and Biological Pharmacy of Guizhou Province, China.
College of Liquor and Food Engineering, Key Laboratory of Fermentation Engineering and Biological Pharmacy of Guizhou Province, Guizhou University, Guiyang, Guizhou 550025, China.
Food Res Int. 2022 Aug;158:111568. doi: 10.1016/j.foodres.2022.111568. Epub 2022 Jun 25.
The usage of traditional crafts during the fermentation process has a great influence on the quality of Jiang-flavored Daqu. This study focused on exploring the impacts of traditional crafts on Daqu microecology through high-throughput sequencing and statistical analyses. These results show that traditional crafts modulated microbial community succession through the regulation of temperature, moisture, and acidity. High temperatures (66 ± 1 °C) were conducive to the growth of microbes that produced flavor compounds, such as Bacillus and Thermoactinomyces. Low moisture content (correlated with 22 genera) and high acidity (8 genera) were mainly responsible for the decreased microbial diversity. Two flipping processes showed significant effects on the internal microecology and microbial metabolism. The first flip of Daqu may assist in regulating the microbial community structure and promoting the enrichment of flavor-functional microorganisms. The second flipping was reasonable for the enrichment of esterifying functional microorganisms, thus enhancing the esterifying power of Daqu with reduced acidity. Furthermore, analysis of the metabolic pathways at different stages of the process showed that the levels of flavor precursors and secondary metabolites within Jiang-flavored Daqu significantly increased during fermentation.
在发酵过程中使用传统工艺对酱香型大曲的质量有很大影响。本研究通过高通量测序和统计分析，重点探讨了传统工艺对大曲微观生态的影响。结果表明，传统工艺通过调节温度、水分和酸度来调节微生物群落的演替。高温（66±1°C）有利于产生风味化合物的微生物如芽孢杆菌和嗜热放线菌的生长。低水分含量（与 22 个属相关）和高酸度（8 个属）主要导致微生物多样性降低。两次翻面过程对大曲内部微观生态和微生物代谢有显著影响。第一次翻面有助于调节微生物群落结构，促进风味功能微生物的富集。第二次翻面有利于酯化功能微生物的富集，从而提高大曲的酯化能力，降低酸度。此外，对不同阶段代谢途径的分析表明，在发酵过程中，酱香型大曲中风味前体和次生代谢物的水平显著增加。
