Albacore T. alalunga T. alalunga abundant abundant

Skipjack Katsuwonus pelamis Katsuwonus pelamis abundant abundant

Common Name Size Size Fat Content, % Fat Content, %

Bluefin to 1500 lb/675 kg to 1500 lb/675 kg 15 15.

Bigeye, ahi 20200 lb/990 kg 20200 lb/990 kg 8 8.

Yellowfin, ahi 3200 lb/190 kg 3200 lb/190 kg 2 2.

Albacore 2045 lb/920 kg 2045 lb/920 kg 7 7.

Skipjack 440 lb/220 kg 440 lb/220 kg 2.5 2.5.

These days, most tuna are harvested in the Pacific and Indian oceans. By far the largest catches are of skipjack and yellowfin tuna, small and medium-sized lean fish that reproduce rapidly and can be netted in schools near the surface. They also provide most of the world's canned tuna, with the solitary light-fleshed albacore (Hawaiian tombo) giving "white" tuna. (Italian canned tuna is often made from the darker, stronger bluefin and from the dark portions of skipjack.) Mackerels The mackerels are small relatives of the tunas. The mackerel proper is a native of the North Atlantic and Mediterranean, typically 18 inches/45cm long and 12 lb/0.51 kg. Like the tuna, it's an energetic predator, with a large complement of red fibers, active enzymes, and an a.s.sertive flavor. It is usually netted in large numbers and sold whole, and deteriorates rapidly unless immediately and thoroughly iced. The mackerels are small relatives of the tunas. The mackerel proper is a native of the North Atlantic and Mediterranean, typically 18 inches/45cm long and 12 lb/0.51 kg. Like the tuna, it's an energetic predator, with a large complement of red fibers, active enzymes, and an a.s.sertive flavor. It is usually netted in large numbers and sold whole, and deteriorates rapidly unless immediately and thoroughly iced.

Swordfish The billfish are a family of large (to 13 ft/ 4 m and 2,000 lb/900 kg), active predators of the open oceans, with a spear-like projection from their upper jaw and dense, meaty, nearly boneless flesh that has been sought after for thousands of years. The preeminent billfish is the swordfish, whose Atlantic stock is thought to be down to less than a tenth of its original size and in need of protection. Swordfish have a dense, meaty texture and keep unusually well on ice, as long as three weeks.

Flatfish: Soles, Turbot, Halibuts, Flounders Flatfish are bottom-dwelling fish whose bodies have been compressed from the sides into a bottom-hugging shape. Most flatfish are relatively sedentary, and therefore are only modestly endowed with the enzyme systems that generate energy for the fish and flavor for us. Their mild flesh generally keeps well for several days after harvest.

The most prized flatfish is Dover or English sole, the princ.i.p.al member of a family found mainly in European waters (lesser U.S. flatfish are often misleadingly called sole). It has a fine-textured, succulent flesh said to be best two or three days after harvest, a trait that makes it an ideal fish for air-shipping to distant markets. The other eminent flatfish, the turbot, is a more active hunter. It can be double the size of the sole, with a firmer flesh that is said to be sweetest in a freshly killed fish. Thanks to their ability to absorb some oxygen through the skin, small turbot are farmed in Europe and shipped live in cold, moist containers to restaurants worldwide.

The halibut is the largest of the flatfish and a voracious hunter. The Atlantic and Pacific halibuts (both species of Hippoglossus Hippoglossus) can reach 10 ft/3 m and 650 lb/300 kg, and their firm, lean flesh is said to retain good quality for a week or more. The distantly related "Greenland halibut" is softer and fattier, and the small "California halibut" is actually a flounder.

From the Waters to the Kitchen The quality of the fish we cook is largely determined by how it is harvested and handled by fishermen, wholesalers, and retail markets.

The Harvest As we've seen, fish and sh.e.l.lfish are a more delicate and sensitive material than meat. They're the animal equivalent of ripe fruit, and ideally they would be handled with corresponding care. The reality is otherwise. In a slaughterhouse it's possible to kill each animal in a controlled way, minimize the physical stress and fear that adversely affect meat quality, and process the carca.s.s immediately, before it begins to deteriorate. The fisherman has no such mastery over the circ.u.mstances of the catch, though the fish farmer has some.

Harvest from the Ocean There are several common ways of harvesting fish from the wild, none of them ideal. In the most controlled and least efficient method, a few fisherman catch a few fish, ice them immediately, and deliver them to sh.o.r.e within hours. This method can produce very fresh and high-quality fish - There are several common ways of harvesting fish from the wild, none of them ideal. In the most controlled and least efficient method, a few fisherman catch a few fish, ice them immediately, and deliver them to sh.o.r.e within hours. This method can produce very fresh and high-quality fish - if if they are caught quickly with minimal struggle, expertly killed and cleaned, quickly and thoroughly iced, and promptly delivered to market. But if the fish are exhausted, processing is less than ideal, or cold storage is interrupted, quality will suffer. Far more common are fish caught and processed by the thousands and delivered to port every few days or weeks. Their quality often suffers from physical damage caused by the sheer ma.s.s of the catch, delays in processing, and storage in less than ideal conditions. Factory-scale trawlers and longliners also harvest huge numbers of fish, but they do their own processing on board, and often clean, vacuum-pack, and freeze their catch within hours. Such fish can be superior in quality to unfrozen fish caught locally and recently but handled carelessly. they are caught quickly with minimal struggle, expertly killed and cleaned, quickly and thoroughly iced, and promptly delivered to market. But if the fish are exhausted, processing is less than ideal, or cold storage is interrupted, quality will suffer. Far more common are fish caught and processed by the thousands and delivered to port every few days or weeks. Their quality often suffers from physical damage caused by the sheer ma.s.s of the catch, delays in processing, and storage in less than ideal conditions. Factory-scale trawlers and longliners also harvest huge numbers of fish, but they do their own processing on board, and often clean, vacuum-pack, and freeze their catch within hours. Such fish can be superior in quality to unfrozen fish caught locally and recently but handled carelessly.

Harvest in Aquaculture By contrast to the logistical challenge posed by fishing, consider the care with which salmon are harvested in the best aquaculture operations. First, the fish are starved for seven to ten days to reduce the levels of bacteria and digestive enzymes in the gut that may otherwise accelerate spoilage. The fish are anesthetized in chilled water saturated with carbon dioxide, then killed either with a blow to the head or by bleeding with a cut through the blood vessels of the gill and tail. Because the blood contains both enzymes and reactive hemoglobin iron, bleeding improves the fish's flavor, texture, color, and market life. Workers then clean the fish while it's still cold, and may wrap it in plastic to protect it from direct contact with ice or air. By contrast to the logistical challenge posed by fishing, consider the care with which salmon are harvested in the best aquaculture operations. First, the fish are starved for seven to ten days to reduce the levels of bacteria and digestive enzymes in the gut that may otherwise accelerate spoilage. The fish are anesthetized in chilled water saturated with carbon dioxide, then killed either with a blow to the head or by bleeding with a cut through the blood vessels of the gill and tail. Because the blood contains both enzymes and reactive hemoglobin iron, bleeding improves the fish's flavor, texture, color, and market life. Workers then clean the fish while it's still cold, and may wrap it in plastic to protect it from direct contact with ice or air.

Flatfish Family RelationsThere are many flatfish, and even more names for them; this list includes only the more common. The names are often misleading: American waters don't harbor true soles; some halibuts aren't halibuts or turbots turbots.

True European soles

Dover, English sole

Solea solea Solea solea

French sole

Pegusa lascaris Pegusa lascaris

Other European flatfish

Turbot

Psetta maxima Psetta maxima

Atlantic halibut

Hippoglossus hippoglossus Hippoglossus hippoglossus

Plaice

Pleuronectes platessa Pleuronectes platessa

Flounder

Platichthys flesus Platichthys flesus

West Atlantic flatfish

Halibut

Hippoglossus hippoglossus Hippoglossus hippoglossus

Winter, common flounder, lemon sole

Pseudopleuronectes america.n.u.s Pseudopleuronectes america.n.u.s

Summer flounder

Paralichthys dentatus Paralichthys dentatus

Greenland halibut or turbot

Reinhardtius hippoglossoides Reinhardtius hippoglossoides

East Pacific flatfish

Petrale sole

Eopsetta jordani Eopsetta jordani

Rex sole

Glyptocephalus zachirus Glyptocephalus zachirus

Pacific sand dab

Citharichthys sordidus Citharichthys sordidus

Pacific halibut

Hippoglossus stenolepsis Hippoglossus stenolepsis

California halibut