FERMENTED FOODS
Mackerel is an important part of the diet in Obama. The fish has historically been abundant in nearby waters, and is a valuable source of animal protein for people in the region. To sustain their diet for winter and stormy days when fishing boats could not sail, people made a style of preserved fish called heshiko. It is often made from mackerel, but also from other varieties of fish. Heshiko is loved for its salty but distinctive flavor and has been eaten in the region for centuries. The dish is significant to regional identity, and is even a feature of Obama’s mascot character, Sabatora Nana-chan, who is always depicted carrying heshiko in her front pocket.
Mackerel heshiko preparation usually begins in late spring, from April through June. The fish are slit open and cured in salt. Maturation takes a few weeks. After midsummer the fish are cured in rice bran, firmly packed into barrels and casks. This is how the dish got its name: the word heshikomu means “to pack down.” Over time, the fish release a liquid rich in umami flavor, and are left to ferment in it for at least six months. As long as they are not exposed to air, the fish can be stored for several years. The result is a tasty preserved traditional food. Heshiko goes well with sake, and is commonly eaten sliced, lightly grilled, or as a condiment of ochazuke, or tea poured over rice.
In Obama, heshiko is also used to make the region’s unique style of nare-zushi, the precursor to modern sushi. The process involves removing the outer layer of skin from the heshiko and soaking the fish in water to remove excess salt. The heshiko are then filled with rice mixed with koji mold and packed in a container layered with more rice and koji mold. When the heshiko are completely buried, a lid and a heavy weight are placed on top. The heshiko then ferment in the lactic acid environment for approximately two weeks. The result is a sweet, flavorful flesh with an aroma sometimes likened to fine cheese. Nare-zushi is made in other regions of Japan as well, using salted fish rather than heshiko. It is a delicacy served around the New Year holiday, and pairs well with sake.