Hamachi Sushi
A Comprehensive Overview of Japanese Amberjack (medium-sized) in Japanese Sushi Cuisine

Hamachi ハマチ, scientifically known as Seriola quinqueradiata, is the Japanese name for a medium-sized japanese amberjack or yellowtail (buri). It is a species of jack fishes in the family of Jacks and pompanos. An individual known as a hamachi measures between 40 and 60 centimeters (ca. 16–24 inch). This size is about half to three quarters of that of an adult buri. Today, hamachi is widely used for sushi and sashimi preparations due to its buttery texture and subtle sweetness.

The taste is full-bodied, minerally and slightly buttery with a distinct sweetness. The light-colored and whitish to pinkish red meat has a pleasant soft texture, is medium firm and thanks to the fat content remarkably tender. The meat of hamachi is equally suitable for nigiri sushi or sashimi.

Hamachi from aquaculture differs significantly from wild caught specimens. The taste of a farmed specimen is lighter and less intense. In addition, the taste depends on the composition of the feed or diet. In farmed fish, especially those with high fat content like hamachi, it is typical that the composition of the feed influences the taste. Depending on the farm, different feeds are used. These range from inexpensive pelleted feeds based on plants (soybean meal or rapeseed oil) to additives that imitate the natural taste (e.g., sardines, anchovies).

The best season for hamachi is from autumn to winter, with the peak in December until late February. The young fish form a shoal and migrate from the north towards Hokkaido, along the Sea of Japan, to the south. The hamachi caught in the winter also carries the name kan hamachi (寒ハマチ). In the winter, caught kan hamachi are particularly fat and therefore tastier.

Hamachi from aquaculture is available in consistent quality all year round.

Traditionally, young and medium-sized hamachi are called buri. In fact, however, the term hamachi is now synonymous with buri from aquaculture breeding (養殖). Wide distribution of commercially farmed hamachi began in the early 1960s and has continued on a large scale ever since. The majority of animals that reach the market after two years of mast are called hamachi.

The Japanese amberjack is commonly referred to as shusseuo (出世魚) fish in Japan. This general term describes fish whose name changes during their growth. The custom originated in the Edo period, when samurai and scholars celebrated their entry into adulthood or social advancement by changing their names. Because of this custom, the name of a fish whose taste changes for the better during its growth has become known as shusseo, and it is said to be used as a good luck charm and as a gift.^[1]

Japanese yellowtail that are classified as hamachi are on average 40 to 60 cm long and have an age of one to three years.

The distribution range of the Japanese amberjack opens up from the south over the East China Sea, in the north over the Kamchatka peninsula and in the east over the northwestern Pacific Ocean to Hawaii. Large populations are found in the Japanese sea as far as to Kyushu. In the late autumn, they move in swarms southwards to spend the winter there.

The Japanese amberjack is a fast swimmer, that as hunt-predacious fish predominantly pursues small fishs, crustaceans and cephalopods during the day. The maximum size is about 1,5 m with a weight of 40 kg, on average most animals have a length of 1 m and a weight of about 8 kg.

Especially in “ordinary” sushi restaurants, farmed buri is generally named hamachi. Mostly this applies to farmed specimen with a size between 4 and 6 kg. The main breeding centers are located in the prefectures of Kagoshima, Ehime and Nagasaki. The market demand is almost completely covered by marine aquaculture. According to the Food and Agriculture Organization of the United Nations (FAO), Japan is the only significant producer of farmed buri or hamachi in the world.