Metabarcoding insights into microbial drivers of flavor development and quality stability in traditional Chinese red pepper sauce: impacts of varietal selection and solar/shade fermentation.

Background: Red pepper sauce is a traditional Chinese condiment, which is rich in nutrients and popular worldwide. However, the changes in the microbial community of red pepper sauce during fermentation and the effects of such changes on quality stability have been under studied. In this study, we systematically analyzed the relationship between the microbial community composition of multiple red pepper sauces and the biochemical indexes. Moreover, we also explored the dynamics of changes in the microbial community composition using metabarcoding sequencing.

Results: Our analysis revealed significant differences in amino acids (AA), lactate, pectin, reducing sugar, flavonoids, phenolics, pigments, and alcohol dehydrogenase (ADH) activity among the six red pepper sauces. Moreover, the relative abundance of bacteria and fungi showed significant differences among multiple red pepper sauces. Among these biochemical indexes, water content, pigment, and capsaicin showed a significant negative correlation with the abundance of multiple bacterial genera. ADH activity showed a significant positive correlation with the abundance of multiple bacterial genera. The content of AA, flavonoid, pectin, and gamma-aminobutyric acid (GABA) was significantly correlated with the relative abundance of multiple fungi such as Rhodotorula, Dipodascus, Leucosporidium, Hannaella, and Coniochaeta.

Conclusions: These results provide a basis for revealing the biological basis of the quality stability and flavor characteristics of red pepper sauce, which are of great significance for further investigation of the fermentation mechanism and control of the product quality of red pepper sauce.