Production of SHOTTSURU (Fish Sauce) by Short-Term Ripening Process and Changes in the Fatty Acid Composition

SHOTTSURU is a traditional fish sauce produced using Japanese sandfish (Arctoscopus japonicus) in Akita prefecture. It is produced over a long ripening period of more than one year. During the aging, polyunsaturated fatty acids such as docosahexaenoic acid (DHA) and Eicosapentaenoic acid (EPA) are oxidatively decomposed. In this study, we prepared fish sauces using Japanese sandfish, cod and saury as raw materials by short-term ripening process (24 hours) at 55℃ under low salt concentration. Since fish sauces are composed of water-soluble ingredients, fat-soluble components are concentrated in the residue. Our results showed that the short-term ripening process suppressed the oxidative decomposition of polyunsaturated fatty acids and enabled to utilize the residue as health food ingredients. The compositions of DHA and EPA were constant during the process although their contents varied among fish species. The fish sauces produced by the shortterm ripening period had good taste and flavor, and their health benefits have been discussed.