Kamebishiya
Kagawa Prefecture has been famous for its soy sauce for centuries, in large part thanks to the island of Shodoshima and the Hiketa area. Now part of the city of Higashi-Kagawa, Hiketa hosted up to 10 soy sauce and sake breweries during its greatest period of prosperity in the Edo period (1603–1867), but of these only Kamebishiya, founded in 1753, remains. The unmistakable smell of soy sauce lingers around the factory’s distinctive deep-red walls, which are roofed with heavy gray tiles.
Kamebishiya is the only soy sauce factory in Japan that still uses the traditional mushiro-koji method of making koji malt, which is a key ingredient in the brewing process. Koji is produced by adding a mold (koji mold, or Aspergillus sojae) to a mixture of steamed soybeans and roasted wheat. The mold spreads throughout the mixture, producing enzymes that further the next step of making soy sauce: fermentation. As making koji the traditional way takes time and effort, most factories have mechanized the process. Kamebishiya, however, continues to rely on the traditional mushiro-koji method, in which the malt is placed on mushiro mats made of soft rush or rice straw and left to incubate for three days. This is done to let excess moisture out and to help the koji maintain an even temperature, improving its quality.
When ready, the koji is mixed with salt and water. This mixture, or moromi, is then poured into large wooden barrels to ferment. The barrels at Kamebishiya, some of which are more than 200 years old, stand inside an eighteenth-century building that provides a home to some 230 types of yeast and other microbes. The microbes are what give Kamebishiya’s soy sauce its distinctive taste. After the fermentation, the soy sauce is filtered and aged for at least two but sometimes up to 10 years. The finished product can be purchased at the brewery shop in another historic building. Eighteen of the Kamebishiya structures, including the shop and the fermentation building, are registered Tangible Cultural Properties.
Another structure of interest within the factory is Nagare World, a detached guest room designed by the sculptor Nagare Masayuki (1923–2018), who had an atelier in Kagawa. Formerly a traditional Japanese room, it was renovated to resemble the dwelling of a merchant family in the Meiji era (1868–1912), with a tiled entrance and glass windows in place of the original sliding doors and shoji screens. The room is decorated with artworks by Nagare and his acquaintances, including a chair by the American architect and furniture designer George Nakashima (1905–1990). Also nearby is Kawashima World, a nineteenth-century storehouse refurbished by the Kagawa-born contemporary artist Kawashima Takeshi (1930–).
