Japanese fish sauce may not be as widely known as its counterparts from Thailand and Vietnam, but demand for it is growing sharply on the heels of the popularity of ethnic cuisine in Japan.

For years, Japanese fish sauce had been eclipsed by the ever-popular soy sauce, and the dominance on the domestic market of Thailand's Nampla-brand fish sauce and Vietnam's Nuoc Mam.

Japanese varieties have been available in limited areas, surviving over the years as "shottsuru" in Akita Prefecture, "ishiru" on the Noto Peninsula of Ishikawa Prefecture and "ikanago shoyu" soy sauce in Kagawa Prefecture.