In Tsukiji Market you will find many wholesalers for tuna fish, an important article of commerce in Japan.
A criterion to grade the quality of a tuna fish is its amount of fat. It should show a nice marbling in the flesh.
The slices considered as the best are taken from the center part of the fish.
The lower belly part named Otoro with its oily meat and Chutoro just behind on the belly towards the tail, are the most expensiv.
In some japanese restaurants you may find Nakochi that looks similar to tartare.
Formerly it was given as a meal to the workers who had to scrape off the remaining meat from the carcase with a spoon.
The cutten tails are giving excample of the quality, the amount of fat and the taste.
The Tuna is filleted with a knife named Maguro bōchō that has an extremly long blade, equal to the length of a tuna fish. It enables to slice the filet in one cut.
A Tunafishs weight comes up to 200 kg and the filleting requires two persons as team.
For a precise cut, the knife is held on both ends with a towel as a protection on the blade.
