Construction of synthetic microbiota for reproducible flavor compound metabolism in Chinese light-aroma-type liquor produced by solid-state fermentation

Abstract

Natural microbiota plays an essential role in flavor compounds used in traditional food fermentation; however, the fluctuation in natural microbiota results in inconsistency in food quality. Thus, it is critical to reveal the core microbiota for flavor compound production and to construct a synthetic core microbiota for use in constant food fermentation. Here, we reveal the core microbiota based on their flavor production and cooccurrence performance, using Chinese light-aroma-type liquor as a model system. Five genera, Lactobacillus, Saccharomyces, Pichia, Geotrichum, and Candida, were identified to be the core microbiota. The synthetic core microbiota of these five genera presented a reproducible dynamic profile similar to that in the natural microbiota. A Monte Carlo test showed that the effects of five environmental factors (lactic acid, ethanol, and acetic acid contents, moisture, and pH) on the synthetic microbiota distribution were highly significant (P < 0.01), similar to those effects on a natural fermentation system. In addition, 77.27% of the flavor compounds produced by the synthetic core microbiota showed a similar dynamic profile (ρ > 0) with that in the natural liquor fermentation process, and the flavor profile presented a similar composition. It indicated that the synthetic core microbiota is efficient for reproducible flavor metabolism. This work established a method for identifying core microbiota and constructing a synthetic microbiota for reproducible flavor compounds. This work is of great significance for the tractable and constant production of various fermented foods.