Enhancing microbial safety and flavor of fermented peppers through inoculation of distinct lactic acid bacteria and yeasts

This study investigated effects of inoculated lactic acid bacteria (LAB) and yeasts on fermented pepper characteristics. Nine of 16 fermented peppers were selected based on sensory evaluation. Physicochemical analysis found that Saccharomyces cerevisiae Ky and its combination with Pediococcus pentosaceus AO consumed the most reducing sugars, while co-fermentation of Zygosaccharomyces bisporus P11 with Limosilactobacillus fermentum AD enhanced nutritional component production. P. pentosaceus AO and L. fermentum AD exhibited strong antibacterial activity against foodborne pathogens, thereby altering microbiota and reducing pathogenic bacterial abundance in fermented peppers. Volatile metabolomics detected 138 compounds, with esters exceeding 30%. Correlation analysis linked 31 microorganisms to 43 compounds. Cyberlindnera rhodanensis M4 greatly impacted flavor via producing multiple esters. Samples M4, P11AD and M4AS contained 30, 25 and 10 of the top two most abundant esters, respectively. Overall, LAB enhanced microbial safety, whereas yeasts improved flavor. These findings support developing high-quality fermented peppers with defined starter cultures. • Evaluated the individual and combined effects of LAB and yeasts on pickled peppers • P. pentosaceus AO and L. fermentum AD show high activity against foodborne pathogens • P. pentosaceus AO and L. fermentum AD reduce pathogen abundance in fermented peppers • C. rhodanensis M4 and Z. bisporus P11- L. fermentum AD improve flavor by making esters • LAB improve microbial safety while yeasts enhance flavor in inoculated fermentation