Shodoshima Soy Sauce: Kagawa's Centuries-Old Brewing Tradition

Shodoshima, an island in Kagawa Prefecture, has brewed soy sauce for around 400 years, and it's often named alongside Noda in Chiba and Yuasa in Wakayama as one of Japan's historically significant soy sauce regions. The island's mild climate and sea access made it well suited to fermentation, and a number of producers still use large wooden barrels called kioke and natural fermentation that can take well over a year, a slower and increasingly rare method compared to the steel-tank production used for most soy sauce sold nationally.

Wooden-barrel soy sauce tends to taste rounder and more complex than mass-produced versions, with less sharp saltiness and more depth. It's sold in bottles as a regional souvenir, and some producers offer tours or tastings of their aging warehouses, though hours and access vary and are worth checking locally before visiting. This same soy-sauce tradition underpins much of Kagawa's everyday cooking, including the dashi used in local broths — a quieter but equally important part of the prefecture's food identity.