Modulating kimchi taste and fermentation with Latilactobacillus sakei, Leuconostoc mesenteroides, and Weissella koreensis starters.

Interactions between microbial metabolites during fermentation play crucial roles in determining the sensory characteristics and flavor profiles of kimchi. However, the specific contribution of different lactic acid bacteria (LAB) to taste modulation remains unclear. In this study, we employed an integrated e-tongue and metabolomics approach to investigate how Latilactobacillus sakei (LS), Leuconostoc mesenteroides (LM), and Weissella koreensis (WK) influence kimchi's instrumental sensory properties and taste profiles. Using both sterilized and non-sterilized kimchi models, we validated the contribution of these starter strains in controlled and spontaneous fermentation environments. All LAB starters maintained high dominance rates (>80 %), ensuring consistent metabolite production and controlled fermentation dynamics. By modulating the fermentation process, these starters induced significant variations in metabolite profiles, contributing to the development of taste characteristics. Principal component analysis of e-tongue responses and metabolite profiles revealed clear separations among the three groups. The starter groups significantly enhanced umami taste in kimchi, reflected by higher NMS (umami) response values on day 14 (LS: 6.9-7.4; LM: 6.9-7.1; WK: 5.9-6.4), compared to that in the control group (5.2). Metabolomic analysis identified 16 key compounds, including the kokumi compound ornithine, underscoring intricate taste interactions. These findings highlight the critical role of targeted LAB starters in shaping kimchi's instrumental sensory profiles and providing foundational insights into optimizing fermentation processes and advancing customized kimchi production.