Analysis of fermentation control factors on volatile compounds of primary microorganisms in Jiang‐flavor Daqu

Abstract

Chinese Jiang-flavor Baijiu is the most widely consumed liquor. Jiang-flavor Daqu, a fermentation starter, is important sources of key flavors of Jiang-flavor Baijiu. Some microbes play significant roles in flavor formation of Daqu. In order to clarify the microbial population that promotes the formation of Daqu flavor, we use high throughput sequencing technology combined with headspace solid-phase microextraction gas chromatography-mass spectrometry to investigate microbial population and volatile compounds in Jiang-flavor Daqu. In addition, the dynamic changes of physicochemical factors and enzyme activities in Jiang-flavor Daqu were investigated. Correlations between microbial population, volatile compounds, physicochemical factors, and enzyme activities of Jiang-flavor Daqu were disclosed by redundancy analysis and Spearman correlation analysis. A total of 66 volatile compounds were identified and 14 primary microorganisms were selected. Results showed that high temperature environment could promote the formation of acids, aldehydes and ketones, phenols, furans by affecting the growth of Monascus, Trichomonascus, Cutaneotrichosporon, Wallemia, Millerozyma, Nigrospora, Cladosporium, Bacillus, and Pediococcus in the early fermentation stage. While high nitrogen environment was more suitable for the growth of Virgibacillus and Kroppenstedtia, who could promote the formation of pyrazines in the late fermentation stage. Practical applicationsThis study has provided a scientific basis for the directed regulation of Daqu fermentation through physicochemical factors, developed scientific basis for artificially constructing Daqu microbial population and obtaining an easy-to-operate, reproducible fermentation system for Daqu production.

Isolation of Yeast Strains with Higher Proline Uptake and Their Applications to Beer Fermentation

“…Due to its production of carotenoid pigments and preference for aerobic growth, Rhodotorula may not be suitable for beer production. Millerozyma has been reported to be involved in the production of acetic acid, phenylethyl alcohol, 3-furaldehyde, and esters in baijiu, a type of Chinese liquor [27]. Since many non-Saccharomyces yeasts are used in continuous or mixed fermentations, Millerozyma yeast can be used to brew beer with a unique flavor profile.…”

Inoculation of Zaopei with biofortification: Inducing variation in community structure and improving flavor compounds in Nongxiangxing baijiu

“…Bacillus was the dominant bacterial genus in both Daqu and stacking fermentation (Wang, Yang et al., 2019) and was also identified as the primary aromatic‐producing bacteria. As a member of the high‐temperature‐resistant genus, Millerozyma was observed in Jiangxiangxing Daqu (Du et al., 2022), soy sauce (Wei et al., 2013), and soybean paste (Mallet et al., 2012), but there are few studies on the biofortification of Millerozyma farinosa using high esterase‐producing enzymes. The functional strain named Staphylococcus epidermidis YTPW‐4 exhibited high esterase activity, good environmental tolerance, and good safety characteristics (Xu, Yang et al., 2023).…”

Integration of Chemometrics and Sensory Metabolomics to Validate Quality Factors of Aged Baijiu (Nianfen Baijiu) with Emphasis on Long-Chain Fatty Acid Ethyl Esters

“…Aged Baijiu offers a deep and unique flavor, enabling people to appreciate the nuances and changes that occur over time by sampling different years of Baijiu. It is not only a testament to traditional craftsmanship and culture but also a result of continuous innovation within the Baijiu industry, providing consumers with a wide range of choices and a heightened level of enjoyment [ 7 , 8 , 9 ].…”