Japan has a long history of producing fermented foods such as soy sauce, miso paste, and natto soybeans. In Obama, a historic port town in the Wakasa region with a long tradition of commercial fishing, the most well-known fermented foods heshiko and narezushi.
Heshiko is made from salted fish, primarily mackerel. Production begins with the fresh fish, which is cut open, cleaned of organs and blood, and filled with salt. The fish is then put into barrels and compressed with gradually increasing weights for about a week to remove excess liquids. Next, the salt is replaced with rice bran, and the mackerel is placed back into barrels with hot peppers to ward off insects and straw ropes around the rims to keep the seals tight. The heshiko is then left to ferment for approximately one year. Popular ways to enjoy the salty, fermented resulted include pairing it with sake, lightly grilling it, using it for sushi, and adding it to chazuke (green tea or broth poured over cooked rice).
Heshiko can be made into narezushi by washing out the excess salt, stuffing the fish with rice and koji malt, and letting it ferment for a few more weeks. Narezushi is considered by many to be the predecessor of modern-day sushi, one of the most beloved foods in Japan and around the world.
