Utilizing Leuconostoc mesenteroides C6 as a starter culture to improve flatfish-Sikhae fermentation stability and quality.

Sikhae is a traditional Korean fermented fish product rich in microbial diversity and flavor. The fermentation process of Sikhae often yields unstable and variable quality. To address this, this study aimed to evaluate the potential of lactic acid bacteria (LAB) as a starter culture for flatfish-Sikhae fermentation in terms of fermentation stability, microbial community dynamics, and quality improvement. Leuconostoc mesenteroides C6 showed high adaptability to fermentation conditions such as salinity up to 5.0 % and acidity as low as pH 3.0. L. mesenteroides C6 significantly reduced the pH, and increased acidity during the initial fermentation stages and maintained high LAB counts, maintaining a stable fermentation process. These physicochemical changes stabilized the fermentation conditions. Microbial community analysis revealed that L. mesenteroides C6 enhanced the dominance of Leuconostoc spp., resulting in a more repressed and stable microbial community. Starter C6 improved sensory characteristics, such as the disappearance of the fishy smell and enhancement in flavor and texture, resulting in an overall preference. In addition, based on the multivariate analysis between variables, a correlation analysis among these variables, such as microbial stability and quality indicators, was assessed. The findings of this study suggest L. mesenteroides C6 as a promising starter culture for enhancing the quality and fermentation of flatfish-Sikhae and provide novel insights into the application of LAB in traditional Korean fermented foods, opening new avenues for modern quality management, optimization of fermentation control, and industrialization.