A single bite of the same bluefin tuna differs greatly depending on the part of the fish it came from.
The body of the fish is broadly categorized into the dorsal (back) and the ventral (belly) sides, which taste completely different. Of course the meat near the head tastes completely different from the meat near the tail. If you dig even deeper, there are parts that aren’t as well-known as the Otoro (fatty), Chutoro (medium fatty) and Akami (lean) tuna meats. We’d like to explain those now.
“Hachinomi (ハチの身) or Tsunotoro Nouten” is the meat from the crown of the head. It is fatty and rich and also called “Head Toro”. Only about 1kg of this precious meat can be taken from even a very large fish, and it is only shared with regular, loyal customers.
“Kamatoro (カマトロ)” is taken from behind the jaw. It is known as “shimofuri (霜降り)” or marbled meat. There are no veins in this part so the meat is soft and the marbling is more detailed than Otoro, so it is sticky and melts in your mouth. The balance of fat and sweetness in this part is unparalleled. It can be said that otoro (such as shimofuri and jabara) of tuna is the representative part of toro tuna. This is an image of the shimofuri on the right, and the jabara (蛇腹) on the left.
“Chiai (血合い)” is the part with the most veins, so it is a dark red color. It has a strong odor of blood and has multiple times the acidity of the lean meat, so it is not used as a sushi topping.
“Chiai Gishi (血合いぎし)” －Located right next to chiai, this is the meat you can taste the umami of the rich red meat and the sweetness of toro fat at the same time.
“Wakaremi (分かれ身)” is a precious part with very little meat found next to the dorsal fin. The part especially close to the dorsal fin is popular and called “Setoro (背トロ)”. Setoro has both the umami of akami and the umami of fat. The fat isn’t overbearing so you can eat a ton. However, this part is hard to get, even in high-quality tuna and is not available except to regular customers in almost all sushi restaurants.
A sushi chef, Hiroyuki Sato, serves a tossaki hand roll as the first sushi piece of the course. “Tossaki (突先)” is an exclusive cut of tuna that goes well with sushi rice using red vinegar, which is less sour but has more umami and flavor compared with white vinegar. Because tossaki is the base of the tuna’s head and it moves a lot, there are a lot of muscular striations. Therefore it needs to be prepared using the back of a knife carefully as if peeling it off (Hagashi). It is said that tossaki is a high-tuna-flavor cut. A couple of Sato’s apprentices also offer a hand roll to open up the meal in the same way.
The meat of tuna gets leaner and muscular striations are fewer towards the inner center of the body. “Tenpa (天端)”, surrounding the spine, is deeper in color and tastes stronger. It features the tender texture coming from the finest meat quality. This is also called Tenmi (天身).
“Hohoniku (ホホ肉)” or cheek meat is taken from below the eye, seasoned, grilled and made into gun-kan rolls. The taste is enhanced in this part by grilling.
“Hireshita (ヒレ下)”－Located right above the first pectoral fin. Characterized with the tender meat which is relatively low in fat content but rich with umami flavor. This truly is the valuable part of whether there will be even enough for 10 pieces of sushi from an over 200 kg tuna.
If you are fortunate enough to get an opportunity to taste these, you can take it as proof that you have been accepted as a regular and loyal customer. It is difficult to distinguish these parts by appearance alone, so make sure you try them at a sushi restaurant you can trust. Just for your reference.
We hope this information will be helpful.
Revision date: June 19, 2020