After bloodletting the fish on-board and extracting their innards, the fish are frozen as-is on the ship at -60°, ensuring that most of those caught are of an especially high grade. With the development of advanced freezing technology, there are numerous cases in which frozen tuna's flavor is held in higher esteem than raw tuna, which poses numerous severe challenges in distribution and handling.

It is also known as Indian Tuna, Bluefin tuna is well known as premium tuna. Also like bluefin tuna, it contains lean meat, chutoro fatty meat, and otoro fatty meat, and possesses a strong and delicious flavor. The fat is sweet as well, and is often used by experienced chefs in high-grade restaurants. This premium tuna is distributed in low quantities and fades in color quickly due to being so vivid, and is thus rarely seen.

In Japan, the word "tuna" is indelibly associated with bluefin tuna. Bluefin tuna is what is served at all premium sushi restaurants, and is the undisputed king of tuna. The texture of its meat has the richest depth of flavor of all tuna, and its bountiful fat content and sheer quality of its flavor has drawn countless people to it. A single fish can contain otoro, chutoro, and toro fatty meat in its stomach depending on the part and how the fat is distributed, which gives tuna a myriad of delicious flavors and only adds to its charm.

Since these tuna are grown in a fish preserve, they have much more fat due to their inevitable lack of exercise. This means that their meat is tender and devoid of lean tuna, making their entire bodies toro fatty meat. Though this makes for a deliciously pleasing texture the moment you take a bite, their flavor is a bit weaker compared to their wild counterparts. However, thanks to recent developments in fishery technology, fish are being raised now that are on par with their wild counterparts.