No vinegar. Salted fish and rice are packed together and left to the lactic fermentation in the rice, which is how sushi worked before anyone thought of speeding it up with acid. Around Arida and Hidaka they use mackerel. From Kushimoto down to Shingu it is saury or sweetfish, whatever the local water provides.

Mackerel is salted for over a month, then desalted across a full day. The rice is deliberately old rice, kept from a previous harvest, because it holds together and can be packed hard. It is cooked with salt, pressed around the fish, wrapped tightly in leaves chosen for their antibacterial properties, and tied with cord.

The bundles go into a wooden tub, packed until there is no space left, and a weight goes on top. After about five days the smell arrives. Everybody who describes this dish mentions the smell before they mention the taste, and nobody apologizes for it.

It belongs to the autumn festival. From the eve through the festival day and into the day after, each member of the household gets one, every meal, until they are gone. A food that takes a month to make and is then eaten steadily for three days by people who know exactly what they are in for.