Effect of lactic acid bacteria on mackerel (Pneumatophorus japonicus) seasoning quality and flavor during fermentation

This study assessed the influence of lactic acid bacteria (LAB) on the physicochemical characteristics of low-salt fermented Mackerel (Pneumatophorus japonicus) seasonings. Key volatile compounds and their formation pathways were analyzed. The flavor of LAB-fermented mackerel seasonings was superior to that of traditional fish sauce, with sensory evaluation scores of 6.5–7.9 and 6.4, respectively. However, the reason for the improved flavor after inoculation with LAB was unclear. Latilactobacillus sakei, (LS1), which was selected from fermented aquatic products, and 2 other common LAB (Lactiplantibacillus plantarum LP1 and Weissella cibaria WC1) were used as starters to investigate the influence of LAB on the formation of flavor substances in mackerel seasonings during fermentation. Aroma extract dilution analysis was used to preliminarily identify the odor-active compounds of the mackerel seasonings. Key odor-active compound quantitation and odor activity value (OAV) calculations were performed to further detect the components impacting the overall odor profile (OAV ≥ 1). These compounds included (E)-2-nonenal, (E,E)-2,4-decadienal, (E)-2-decenal, 1-octen-3-ol, and (E,E)-2,4-nonadienal. Furthermore, the correlations between odor-active compounds and sensory characteristics were evaluated by partial least squares regression (PLSR). The results suggested that 2,4-nonadienal, furfural, (E)-2-octenal, hexanal, and (E)-2-decenal had a positive correlation with pleasant flavor attributes, and LS1 was more conducive to the formation of these compounds than LP1 and WC1.