Konoshiro Sushi
A Comprehensive Overview of Dotted Gizzard Shad in Japanese Sushi Cuisine

Konoshiro, scientifically known as Konosirus punctatus, is a medium-sized spotted Pacific herring that is mainly found in the coastal waters of the western Pacific. Medium-sized specimens, referred to as kohada, are predominantly preferred for sushi. The small to medium-sized fish, which is characterized by its shiny silvery skin and the dark, dot-shaped markings on its body, plays an important role in Japanese cuisine, particularly in the preparation of sushi.

Konoshiro or kohada is highly prized for its distinct taste qualities, which are characterized by a fine blend of fattiness and a hint of bitterness. It is considered one of the classic representatives of “blue-backed fish” as well as the “shiny fish” for traditional sushi. Preparing the fish requires skill and knowledge, as boning, marinating and the visually appealing presentation of the fish are important.

The meat with its characteristic skin is not only a popular ingredient for the preparation of sushi or sashimi, it is also a symbol for the philosophy of edomae sushi among connoisseurs and chefs alike. Because of its fresh, shiny appearance, it is considered one of the most beautiful sushi dishes, which reaches its peak in flavor only when properly prepared and combined with sushi rice.

When the meat of konoshiro is salted and marinated in vinegar, an exceptionally full-bodied taste is created, which harmonizes wonderfully with the subtle sweetness of sushi rice. In addition, the marinating process reduces the strong taste and softens any bones that may still be present. The duration of application and dosage of salt and vinegar are adjusted according to the size of the fish, the amount of fat and the season, so that a lot of experience in preparation is required. It is said that hardly any other fish can vary so much in taste by treatment with salt and vinegar. Therefore, it is said that konoshiro or kohada is a measure of the skill of the chef or the quality of a sushi restaurant, as the taste changes significantly depending on the amount of vinegar and salt used. Depending on the size of the fish, either the whole fish can be used or up to four whole specimens of smaller size.

The taste of kohada sushi is characterized by mineral aromas accompanied by a buttery sweetness and subtle acidity. The range of possible side dishes or garnishes is wide and extends from an extraordinarily fine preparation of egg yolk or shrimp paste to yuzu citrus fruit and an individually refined seasoning sauce. The sauce is often applied as a thin glaze to the fish before it is served as nigiri sushi. Besides its wonderful rich and fatty taste, the meat is rich in proteins, essential fatty acids and trace elements.

The spawning season begins in early spring and ends in early summer, with some fish spawning twice or more.^[1] The season for small fish named shinko starts in July and ends in August. Medium-sized specimens with the name kohada are mostly caught between August and September. Large specimens of the konoshiro are caught all year round, but are most palatable in the winter period from November to February.

Konoshiro belongs in Japan to the “rising or ascending fishes”, this refers to fishes that change their name depending on size and age. A dotted gizzard shad carries the name shinko up to about 5 cm total length, from a size of 7 to 10 cm it is called kohada. As soon as it reaches 13 cm, it carries the name nakazumi, in order to then be called konoshiro as adult fish from a length of 15 cm. For the preparation of a nigiri sushi, depending on the size of the fish, either whole or multiple specimens of the size shinko are used. Large specimens are rarely used for the preparation of sushi or sashimi, but are suitable for other types of preparation.

If you look at the growth in value of the konoshiro, you can almost mockingly claim that it is a “descending fish”, because with increasing size its value and thus its selling price decreases. Especially for the preparation of sushi, smaller sizes like kohada or shinko are appreciated.  

The distribution area extends along the coast of the Japanese archipelago over the Korean peninsula to the East China Sea. The dotted gizzard shad is only slightly migratory and does not change its habitat significantly during its life cycle. Its diet consists mainly of plankton, diatoms and small crustaceans. 

Konoshiro is only of minor economic importance. According to the Food and Agriculture Organization of the United Nations (FAO), Japan is the only country that catches it in industrially relevant quantities. Since 2005, South Korea has been producing konoshiro from aquaculture.^[2]