Classification of bluefin tuna by age and weight – Story of the most expensive tuna fish of the world – Ichiban maguro by Kiyoshi Kimura in 2019
Classification of Bluefin tuna by age and size – mejimaguro, chubomaguro, shibi maguro
Depending on the size and age of the bluefin tuna, bluefin tuna are classified to three more groups. The meji(めじ), chubo(中坊) and the shibi(鮪). The meji tuna or the mejimaguro refers to the young bluefin tuna younger than 3 years old and less than a meter.
Mejimaguro or young bluefin tuna is very lean and has less oil and fat content than the chubo maguro and the shibi maguro.
Mejimaguro often have a bit sour and acidic taste compared with maguro because when caught mejimaguro don’t often have their blood drained.
Still, mejimaguro has its own soft tender texture with lean meat. The chubo maguro means medium sized tuna or average. Usually the chubo maguro are less than 50kgs about 110 pounds and about the age between 3~5 years.
A fully grown bluefin tuna is called the shibi maguro that are sexually mature. Thus shibi maguro are heavier and larger than the shibi and meji tuna.
Classification of Bluefin Tuna by Weight - 上 san, 40上, 50上,60上,70上,80上
High quality and expensive bluefin tuna are usually the heavier bluefin tuna, however there are other qualities checked as well such as the distribution of fat whether the blood was well drained etc.
In general the ‘fatter’ the fish, the higher chance the flavor is better. Thus short and fat fish are generally considered high quality.
The concept of 上, san refers to the weight of the quarter(1/4) of the bluefin tuna carcass. Bluefin tuna are divided into 2 back loins, 2 belly cuts and the head with the bones. 上,san refers to the kg weight of one of the carcass cuts whether the back loin or the belly cut.
Usually the bones and head, 2 back loins and 2 belly cuts are 1/5 of the total bluefin tuna weight. Thus a 50上 tuna is about 250kgs~300kgs while the 60上 tuna is about 300kgs~360kgs. 80上 bluefin tuna are likely to be larger than 400kgs.
However the 上 unit may differ from manufacturer but they all refer to the approximate weight range of the 1/5 cut of a bluefin tuna.
Classification of the belly toro cuts – Kamatoro, #1 Toro, #2 Toro
The belly loins(belly toro cuts) or the semitoro(semitoro is the bluefin tuna cut where only the belly parts are distributed) of bluefin tuna are also divided into several classes.
The Kamatoro and the numbered toro usually have the Otoro and Chutoro evenly distributed and these are the prime cuts of the bluefin tuna.
The closer to the head, the lower the number toro is and the more expensive. The Kamatoro is the most expensive followed by the number 1 toro, number 2 toro etc.
The number counting may differ by the manufacturer, however in Japan the each number toro is divided by 20centimeters along the anterior-posterior axis(head to tail).
After the number 5 toro, the numbers aren’t counted and the number 5 toro is considered the least quality among the belly parts. Stil even the number 5 toro has good fatty contents.
Most expensive bluefin tuna species – Pacific bluefin tuna
Among the three bluefin tuna species, the Pacific bluefin tuna is the most expensive followed by the Atlantic bluefin tuna then the Southern bluefin tuna. The Southern bluefin tuna has less fat and it is leaner than the other two species.
The Pacific bluefin tuna is more expensive than the Atlantic bluefin tuna not because of quality of the tuna itself but because most bluefin tuna is consumed in Japan.
The wild caught Pacific bluefin tuna that could be distributed and reach the market without freezing made the Pacific bluefin tuna the most expensive bluefin tuna species. Atlantic bluefin tuna inevitably have to reach the Japan market frozen.
HatsuSeri – Japan’s New Year’s first bluefin tuna auction
はつせり, 初競り means the first sale and it refers to the first Tuna action of the New Year. Hatsu Seri became a tradition in the Japan tuan market as it became a symbol for fortune and New Year’s Luck.
Usually, the first bluefin tuna put into auction at the Hatsu Seri is the Ichiban Maguro that means the number one tuna. 一番マグロ.
The most expensive bluefin tuna sold – Ichiban Maguro
The most expensive Ichiban Maguro was a Pacific Bluefin Tuan caught in Oma Japan that was 612 pounds, 278kg that sold at a record of 333.6 million Japanese yen in 2019.
The chairman Kiyoshi Kimura the chairman of the famous sushi restaurant chain Sushi Zanmai made this bid at the Tokyo’s largest fish market the Toyosu fish market.
The competition between the Itamae Sushi backed up by Hong Kong capital and the Sushi Zanmai group from Japan native capital triggered this expensive auction over the Ichiban Maguro.
How much was a piece of the most expensive bluefin tuna sold at?
Despite the most expensive pacific bluefin tuna’s astonishing costs, Kiyoshi Kimura the chairman Kiyoshi Kimura sold this bluefin tuna’s otoro at a normal price about 300~400 Japanese yen price.
The Ichiban maguro may have been expensive, but it brought great promotional effect across Japan and worldwide.
Competition between Itamae Sushi and Sushi Zanmai over the Ichiban Maguro – Hong Kong vs. Japan
The Itamae Sushi brand was created and supported by capital and funds from Hong Kong. The chairman of Itamae Sushi Rickie Chen won the Ichinban maguro since 2008 for 4 years in a row and took the bluefin tuna to Hong Kong.
Kiyoshi Kimura, the chairman of the Sushi Zanmai brand couldn’t tolerate the Ichiban maguro being imported to a foreign country and a competition sparked between the two sushi chains of Hong Kong and Japan.
This competition led to Kiyoshi Kimura in paying 33 million yen for the most expensive bluefin tuna and the most expensive fish of the world. Yet, both chains have increased sales and revenue as the competition was highlighted every year that became a great promotion.
The competition between these brands stopped and both were rather passive in participating for the Ichiban maguro bid between 2021~2025.
