How Japanese Dried Bonito Is Made

Katsuobushi, the intensely dried bonito used in Japanese cooking, is made at Kanesa Katsuobushi Shoten, a workshop in Nishi-Izu established in 1882. Fifth-generation craftsman Yasuhisa Serizawa continues to use tebiyama, a traditional hand-fired smoking technique dating back roughly 200 to 300 years to the Edo period. Only a small number of bonito producers in Japan still practice this method, making the workshop an unusually direct link to an older craft.

The process takes more than six months. Fresh bonito is filleted and boiled for about 90 minutes, then smoked and dried over a wood fire more than ten times. The fish is patched with bonito paste, treated with koji mold, and repeatedly dried in the sun over several months. Tebiyama uses a deep vertical pit, with local woods such as oak, sawtooth oak, and cherry burned at its base; the open flame’s high heat is said to seal in the fish’s umami. By the end, the bonito becomes exceptionally hard, nearly like wood, with a polished, jewel-like appearance. The account highlights both the labor and patience behind a familiar ingredient and the rarity of preserving this particular smoking technique.