Effects of different fermentation starter cultures on the quality of fish sauce prepared from deep-sea smelt

This study investigated deep-sea smelt fish sauces made with three types of starter cultures to produce a high-quality product that contains low histamine levels. The starter cultures included lactic acid bacterium Tetragenococcus halophilus for soy sauce and T. halophilus strains 8-25 and 14-1 that do not receive the histidine decarboxylase gene, isolated from fermented marine foods. The addition of these bacteria reduced the pH of the fish sauce mashes (moromis) to below 5.0 in the first 21 d. This pH level was maintained until the end of fermentation. Throughout fermentation, histamine-producing bacterial counts and histamine levels in the moromis were below 9.3 × 10 most probable number (MPN)/g and 113 mg/L, respectively. A principal component analysis of the final products revealed that taste, which was obtained using a taste sensor, and quality indicators (physicochemical and extractive components) differed among the three products.