Yellowfin tuna (Ahi tuna) Nutrition facts

Yellowfin tuna (also known as Ahi tuna) is a major commercial species of tuna found in tropical and semi-tropical waters across all major oceans.

It derives its name from the bright golden-yellow coloration of its dorsal, anal, and tail fins, as well as the conspicuous lateral lines running along its sides.

Yellowfin's moderately oily, firm, and mild-flavored reddish-brown flesh is highly prized in Japanese cuisine for sashimi and is also popularly consumed as canned "light tuna" in the United States.

Scientific Name: Thunnus albacares. Family: Scombridae.

Ahi tuna (Thunnus albacares).

Description

Yellowfin tuna belong to the larger species of tuna. Their bodies are robust and shaped like torpedoes, allowing them to swim swiftly at speeds of up to 40 miles per hour.

They possess notably long second dorsal and caudal fins. The pectoral fin is also elongated, extending beyond the base of the second dorsal fin but not surpassing its end.

Their backs range from black metallic to dark blue, with a transition from yellow on the sides to silvery on the belly. A distinct golden-yellow stripe runs along their sides.

White, broken, nearly vertical lines often adorn their sides and belly. Their dorsal and anal fins, along with finlets, are bright yellow with black borders.

The lifespan of yellowfin tuna ranges between 6 and 10 years. Adults typically measure about 100-140 cm in length and weigh 40-70 lbs. Purse seine fishing vessels capture the majority of yellowfin tuna, accounting for about 50% of those caught.

Habitat

Yellowfin tuna are pelagic marine fish found throughout the tropical and semi-tropical Pacific, Atlantic, and Indian Oceans.

They prefer warm waters and are typically located in the top 100 meters of the ocean, often congregating around drifting objects.

Yellowfin tuna are fast-swimming predators that prey on a wide variety of fish, including pilchard, anchovy, mackerel, and other tuna species such as skipjack, as well as crustaceans and mollusks such as cuttlefish, squid, shrimp, octopus, and the larval stages of lobster and crabs.

Biology

Yellowfin tuna reach maturity between 2 and 5 years of age. They spawn in warm, open water close to the surface and are multiple spawners. Females release eggs in several batches, occurring approximately once every 2 to 3 days, with peak spawning activity observed in summer.

Health Benefits of Ahi (Yellowfin) Tuna

Yellowfin tuna, also known as Ahi, is a moderately oily marine fish. Its pinkish-red meat is rich in protein, essential fatty acids, minerals, and fat-soluble vitamins such as vitamins A, E, and D.
A 3.5 oz (100 g) serving of fresh yellowfin steak provides 109 calories and 24.4 g/100 g (43.5% of RDI) of protein. It contains all the essential amino acids in optimal proportions.
Ahi tuna is low in saturated fats and cholesterol but is a moderate source of polyunsaturated fatty acids (PUFA) and Omega-3 fatty acids. Studies suggest that consuming seafood rich in omega-3 fats, like canned tuna, may help prevent cognitive decline, dementia, depression, neuropsychiatric disorders, asthma, and inflammatory disorders.
Research indicates that omega-3 fatty acids, particularly DHA, play a vital role in the nervous system's development, especially in infants and children.
According to research from Cornell University and the New York Sea Grant Extension Program in 2012, omega-3 fatty acids play a crucial role in reducing blood pressure and heart rate, thus improving cardiovascular function. They also decrease the risk of arrhythmias (abnormal heartbeats) that can lead to sudden death.
Yellowfin tuna contains small amounts of vitamin A (60 IU/100 g). However, its liver is rich in omega-3 essential fatty acids such as eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA), which support healthy mucosa, skin, and hair.
The lean meat of yellowfin tuna is an excellent source of B-complex vitamins such as niacin, pyridoxine (B-6), and B-12. It also provides vitamin E, thiamin, and riboflavin.
Furthermore, yellowfin tuna is a natural source of essential minerals including iodine, selenium, calcium, zinc, potassium, phosphorus, and magnesium. Iodine, particularly, is crucial for thyroid hormone production.
Yellowfin tuna flesh contains only 0.34 ppm of mercury, placing it in the "good choice" category by the US FDA. The recommended consumption is one serving (4 ounces) per week.

See the table below for in depth analysis of nutrients:

Yellowfin tuna, raw, Nutritive value per 100 g. (Source: USDA National Nutrient database)

Principle	Nutrient Value	Percent of RDA
Energy	109 Kcal	5.5%
Carbohydrates	0 g	0%
Protein	24.4 g	43.5%
Total Fat	0.49 g	2.5%
Cholesterol	39 mg	13%
Dietary Fiber	0 g	0%
Vitamins
Folate total	2 μg	0.5%
Niacin	18.5 mg	116%
Pyridoxine	0.933 mg	72%
Riboflavin	0.115 mg	9%
Thiamin	0.118 mg	10%
Vitamin-A	60 IU	2%
Vitamin B-12	2.08 mg	87%
Vitamin-C	0 mg	0%
Vitamin-D	69 IU	11.5%
Vitamin E(α-Tocopherol)	0.24 mg	1.6%
Electrolytes
Sodium	45 mg	3%
Potassium	441 mg	9.4%
Minerals
Calcium	4 mg	0.4%
Iron	0.77 mg	9.6%
Magnesium	35 mg	9%
Phosphorus	278 mg	40%
Selenium	90.6 mg	165%
Zinc	0.37 mg	3.3%
Omega-3 fats (PUFA)
EPA (20:5 n-3)	0.012 g	--
DPA (22:5 n-3)	0.004 g	--
DHA (22:6 n-3)	0.088 g	--

Buying

Yellowfin tuna is available in various forms including fresh (chilled whole fish, loins, fillets), frozen (whole fish, loins), canned, and smoked.

Key processing countries for yellowfin tuna include Thailand, the Philippines, Indonesia, Mexico, Spain, and Italy.

The primary importing countries for yellowfin tuna are the US, Japan, and Europe.

When purchasing canned tuna, look for the "sustainable" label, especially in olive oil. It is often marketed as "light tuna" as opposed to the "light-chunk tuna" of skipjack and the "white tuna" of albacore. For fillets and steaks, opt for at least No. 2 grade and above, while sashimi grade is considered No.1.

Storage Guidelines

Yellowfin tuna tends to dry out rapidly, so it's best to store it in an airtight container and keep it on the bottom shelf of your refrigerator. Fresh tuna flesh typically appears pinkish-red but may darken to a dark brown when frozen, which is normal.

Ensure that tuna steaks are stored at a temperature below 40°F and consumed within 2 days of purchase. If you're unable to consume it within this timeframe, transfer it to the freezer section where it can be kept for up to 3 months until you're ready to prepare it.

Culinary Applications

Yellowfin (ahi) tuna is highly favored for its versatility in cooking. Its firm flesh offers a richer flavor compared to albacore and is leaner and more budget-friendly than Bluefin.

Canned yellowfin tuna is often packed in garlic-infused olive oil, enhancing its flavor profile.

Here are some serving ideas:

Yellowfin tuna-pan seared. Photo credit: Vmiramontes

Create a Ahi tuna Poke dish, a Hawaiian raw-tuna salad, by dicing sashimi-grade Ahi tuna into small cubes. Mix it in a bowl with onions, green onions, soy sauce, sesame oil, chili garlic sauce, and sesame seeds.
Present pan-seared tuna alongside fresh salad greens, ensuring not to overcook.
Indulge in the popular marinated grilled ahi tuna steak, a favorite in restaurants across the United States. Enjoy it either on its own or as a filling for sandwiches.
Prepare the classic American-style tuna casserole.
Utilize the firm texture and mild flavor of Yellowfin tuna for delectable sashimi.
Yellowfin (ahi) tuna, often used as a substitute for other varieties in Italian dishes like vitello tonnato (Piedmontese), pairs excellently with cold veal, anchovies, and capers. It's also a delightful addition to sandwiches, sauces, omelets, and casseroles.

Safety profile

Fresh or frozen Yellowfin tuna contains methyl-mercury at a level of 0.354 PPM, earning it a classification as a "Good Choice" fish by the FDA. According to FDA guidelines, individuals, including pregnant women, can safely consume one serving per week from the "Good Choice" list, with one serving equating to 4 ounces for adults.

Comparatively, canned albacore tuna contains 0.350 PPM of mercury, while fresh or frozen bigeye tuna contains 0.689 PPM.

It's important to note that for pregnant women, the U.S. FDA recommends the consumption of only cooked fish and advises against consuming raw fish. (Medical disclaimer)