【Reading】きもじょうゆ

【English Name】Kimo Shoyu (Liver Soy Sauce)

Kimo-joyu (liver soy sauce) is a kind of dipping sauce made by sieving fish liver and combining it with soy sauce and wasabi. It is added mainly to sashimi of filefish (kawahagi) and black scraper (umazura-hagi), and at sushi restaurants it is sometimes served together with white-fleshed nigiri and sashimi.

The basic preparation is to carefully sieve fresh liver and mix in soy sauce and wasabi until smooth. The liver is rich in inosinic acid, and it is said that a synergistic effect of flavor is created when it combines with the amino-acid-type umami of soy sauce.

In the filefish, the weight ratio of liver to body weight is 15 to 20%, far larger than the under 1% of sea bream or the around 1% of mackerel. Because it stores nutrients in preparation for spawning from autumn to winter, the liver enlarges and fat content also increases. Kimo-joyu in this season becomes especially rich in flavor. The liver of the black scraper is also rich in fat, said to have such a low melting point that it melts at around body temperature.

A similar way of eating is "tomo-ae," a cooking method in which the flesh and liver of the same fish are dressed together. It is passed down across the country as a local dish of monkfish (anko), filefish, and the like. The freshness of the liver is important, and generally it is considered safer to heat it before use, but very fresh ones are used raw.