When perusing the fish market counter or menu at a seafood or sushi restaurant, the terms yellowfin, ahi, or bigeye tuna might seem like Latin to people who aren't well-versed in types of fish. What are the differences?
Ahi
Ahi is a species of tuna and is divided into two different types: yellowfin and bigeye. The name comes from the Hawaiian word for fire and references the smoke produced from the fishing line going over the side of the boat so quickly when ahi is caught. The species is valued for not only being a sport fish but also for its delicious flavor. In Hawaii, ahi are most abundant in the spring and summer, but they can be fished year-round. Ahi is common in poke, a signature Hawaiian dish of marinated, cubed, raw fish served over rice.
Yellowfin
The dorsal, anal and finlet fins on a yellowfin tuna are yellow, which is where it gets its name. It has a slimmer profile than bigeye tuna. Yellowfin is known for its mild taste and firm texture, so it's a preferred tuna for sashimi (thinly sliced raw fish). It can be marinated and grilled, too.
Bigeye
Bigeye tuna is also found in tropical and subtropical ocean waters and is popular in Hawaii for eating and sport fishing. It's characterized by its plump body, larger head and unusually large eyes. Because this fish dwells in cooler waters, it has a higher fat content than yellowfin, which is the main distinction between the two. Though yellowfin is widely accepted for sushi and sashimi, bigeye is prized by purists because the extra fat provides a buttery flavor and supple texture. This higher fat content also makes bigeye good for the grill because it won't dry out as quickly.
Nutrition
Ahi is considered a healthy seafood because it's extremely lean. Both yellowfin and bigeye varieties are naturally low in saturated fat and sodium, while rich in vitamins B6 and B12 and phosphorous. They're both good sources of omega-3 fatty acids and magnesium as well. Next time you're grilling burgers or steaks, try adding in an ahi steak. It's heart healthy, tasty and is an extra-lean source of protein.