How to Cut Fresh Tuna
- 1). Lie the fish flat on its side and make an incision at the top of the head that goes deep enough to touch bone. The side of the fish that is facing up will have a protruding fin. Make a slightly curved line that goes from the first incision around the fin. Cut on this path while keeping the blade deep enough to touch bone. Make a mirror image of this incision from the outside of the fin to the bottom of the head.
- 2). Make an incision at the base of the tail in the middle and cut horizontally till you reach the incision you made around the head. When looking down at the fish, the incision should be directly in the middle -- meaning there is an equal amount of visible skin above the incision and below it that spans the entire body of the fish.
- 3). Carefully pull the loin from the bones of the fish. The loin is the boneless portion of edible flesh cut lengthwise from either side of the backbone of a large, roundbodied fish. This is the region to the right of the incision around the head and above the horizontal incision. It will be shaped similar to a triangle. Trim the side of the loin that is still connected beneath the dorsal fin in order to fully remove the loin. The dorsal fin is the fin along the spine of the fish, it will be parallel to the table in this position.
- 4). Carefully lift up the bottom loin and cut along the bottom fin where the loin is still attached. The side of the fish facing up should have no visible meat between the head and the tail at this point.
- 5). Flip the fish over and repeat the entire process. This should yield 4 fish fillets.