Shaping microbial communities and flavor profiles: Effects of native Staphylococcus carnosus and Staphylococcus piscifermentans starter cultures in Chinese dry-fermented sausages.

The metabolic activities of indigenous microbiota play a crucial role in determining the physicochemical, sensory, and safety properties of fermented meat products. In this study, we investigated the effects of two native starter cultures, Staphylococcus carnosus C22 and Staphylococcus piscifermentans C29, on the quality attributes and flavor development of traditional Chinese dry-fermented sausages. Through comprehensive analysis of physicochemical, sensorial, flavor, and microbiological characteristics during ripening, we demonstrated that inoculation with these strains significantly enhanced the sausages' red color intensity and textural properties, accelerated acidification, and reduced residual nitrite levels compared to non-inoculated controls. Volatile compound analysis revealed substantial modifications in flavor profiles, with 40 distinct compounds identified. S. carnosus C22 inoculation generated a broader spectrum of flavor compounds, including esters, ketones, alcohols, unsaturated hydrocarbons, acids, and aromatics, while S. piscifermentans C29 exhibited superior diversity and abundance of esters, alcohols, and acids. Notably, the mixed starter culture combination produced the highest content and diversity of esters, resulting in significantly improved overall flavor quality and sensory evaluations. Microbial diversity analysis indicated that starter culture inoculation shaped a core microbiota dominated by Staphylococcus, Lactococcus, Acinetobacter, Corynebacterium, Latilactobacillus, Enterococcus, and Chryseobacterium. Correlation analysis revealed significant positive associations between key volatile compounds and specific microbial genera including Staphylococcus, Sphingobacterium, Rhodococcus, Dermacoccaceae, Pseudoclavibacter, and Citrobacter. These findings demonstrate the potential of native starter cultures as an effective tool for shaping a functional core microbiota and optimizing flavor profile and overall quality in fermented meat products. This study provides a scientific basis for the industrial-scale production of high-quality, regionally characteristic fermented meats with enhanced organoleptic properties.