Hyakuma Shoten: the largest producer of Honkarebushi in Japan

Photo: bonito sprayed with koji mold

The Satsuma region (now Kagoshima Prefecture) on the island of Kyushu in southern Japan has been renowned for centuries for its production of smoked bonito (skipjack tuna). Yamakichi Kunisawa Hyakuma Shoten, founded in 1947, is Japan's top producer of honkarebushi, manufacturing approximately 70% of the nation's total. Headquartered in Yamakawa, Ibusuki City, the company handles the entire production process to guarantee a high quality finished product. They put an emphasis on using line-caught skipjack tuna (一本釣り) to ensure superior fish quality, and manage all transformation steps internally from smoking the fish, to fermenting it with koji mold, shaving off the unwanted parts and processing the bonito blocks into shavings (katsuobushi) or other products such as dashi powder and bonito floss. 

Photo: blocks of finished honkarebushi

Smoked bonito flakes and dashi readily available in supermarkets and more commercial products normally use a type of a smoked bonito called arabushi (荒節) which is cheaper to produce than the higher quality honkarebushi (本枯節). The distinction between honkarebushi and arabushi (荒節) lies primarily in their refining processes, which in turn affect flavor, aroma and quality. In the case of arabushi, the skipjack tuna fillets are smoked and cooled repeatedly until most of the moisture is removed, but they are not inoculated with mold or subjected to extended fermentation and drying cycles. Because of this, arabushi delivers a strong smoky aroma and a deeper “raw” fish-smoke character, but it lacks the delicate, refined umami developed through enzyme action. On the other hand, honkarebushi begins with a similarly filleted, smoked and cooled fish, but then undergoes further steps: scraping to remove tar and fat, inoculation with specific mold spores (akin to koji-type fermentation), followed by repeated drying and humid cycles over many months. This extended moulding and drying produces fish that is drier, harder, and whose proteins and lipids have been broken down into richer savoury compounds, giving a very pure, refined umami rather than heavy smoke.

Photo: factory visit with Kunisawa family

For real authentic smoked bonito flavours, try Yamakichi Kunisawa Hyakuma Shoten's products by visiting our online store!