Effects of adding various salted seafood (jeotgal) types on the microbial, metabolic, and sensory dynamics of kimchi during fermentation.

Kimchi is a traditional Korean fermented dish in which salted seafood is widely used; however, its specific role in fermentation remains unclear. This study investigated the impact of four salted seafoods (anchovy, cutlass offal, yellow croaker, shrimp) on the physicochemical, microbial, metabolic, and sensory properties of kimchi compared to a no-seafood control. Samples were fermented at 4 °C for 6 weeks. Salted seafood accelerated acidification and increased total and amino nitrogen, hypoxanthine, inosine, and free amino acids (e.g., glutamic acid, γ-aminobutyric acid). Halophilic lactic acid bacteria, including Tetragenococcus halophilus, were enriched in anchovy kimchi at early stages, whereas L atilactobacillus sakei dominated all samples at mid-late fermentation. Metabolomic profiling and electronic tongue analysis revealed enhanced accumulation of flavor-related metabolites and stronger umami and sourness in seafood-supplemented kimchi, associated with organic acids and microbial succession. Overall, salted seafood functions as both a flavor enhancer and natural microbial starter in kimchi fermentation.