Fish Facts

rancidity: The oxidation of the natural oil in the fish, making the fish unpalatable

refreshed: Also "previously frozen." Seafood that has been frozen, often in blocks, then slacked out for resale.

roe: Most fish species grow their eggs in a sac in the abdomen, and the roe of some species is considered a delicacy in various countries. Sturgeon roe, or caviar, is the best known and most expensive in the U.S., but cod, herring, mullet, Pollock, salmon and shad all produce roe prized by various regional and ethnic groups.

round: Whole, ungutted fish; shrimp that has been peeled but not split or deveined.

Sashimi: Japanese-style raw fish cut into various forms. Also a term used to grade certain species such as Swordfish. When frozen, sashimi is held at extremely low temperatures down to -50 degrees.

Sashimi: Japanese-style raw fish cut into various forms. Also a term used to grade certain species such as Swordfish. When frozen, sashimi is held at extremely low temperatures down to -50 degrees.

Scombroid: Organic substance produced in the tissue of a fish that has not been properly cooled after harvest. Histamine concentrations produce food-poisoning symptoms in humans. Poorly handled Mahi Mahi, tuna and bluefish are the most commonly implicated species. Also called scombroid poisoning due to its association with the tuna family. See histamine.

Scrod: Size designation for cod, haddock, Pollock and cusk. Means "small," usually under specific poundage. Scrod is not a species of fish; sometimes spelled schrod.

sections: The three walking legs and one claw on one side of king, snow or Dungeness crab, all attached at the shoulder.

semibright: Chum salmon that has been harvested in freshwater, on its way to spawn. Semibrights are also called "brights."

Shatterpack: A box of frozen fish fillets separated by interleaved polyethylene sheets. Dropping the box, "shattering" the pack, will separate fillets.

shelf life: The expected amount of time a seafood product will remain in high-quality condition for consumption. In general, the higher the fat content, the more prone the product is to spoilage and flavor changes. Cold temperatures retard most of these changes.

shellfish: Two major groups of seafood are called shellfish. Mollusks include clams, oysters, mussels, conch, snails and scallops. Crustaceans include shrimp, crabs, lobster and crawfish. Squid and octopus are generally considered shellfish as well.

shrink: Natural weight loss of seafood due to seepage or fluids draining from product, also called drip or purge. Also, loss of seafood product or profitability due to other means, such as discarding seafood too old to sell.

Silverbright: A term referring to chum salmon that have been harvested at sea rather than in freshwater.

skinned: Some species of fish are skinned rather than dressed, such as catfish and eels.

slacked out: Frozen seafood that has been thawed. Also called "refreshed".

smoked: Fish cured by the action of smoke produced from slowly burning wood or other material, to partly dry the product and impart a smoky flavor.

snap-n-eats: Crab legs that have been cooked, frozen and scored through the shell so they can be hand-cracked for easy eating.

steak: A cross-sectional slice of a fish, usually 1/2 to 2 inches thick and containing a section of the backbone. Steaks usually yield an edible portion of about 86% to 92%. Salmon, halibut, swordfish and other large fish are commonly processed and sold as steaks.

STP: additive, sodium Tripolyphosphate, used on fish and shrimp to retain moisture.

sushi: Thin, Japanese-style slices of raw fish placed on boiled rice, flavored with rice wine vinegar and rolled in seaweed (nori). The rolls are sliced into bite-sized portions.

tail: Fish portion, which resembles the tail of a fish, boneless, usually breaded or batter-dipped, raw or precooked. Weights vary from 3-1/2 to 6 oz. Sometimes the entire tail, bone-in, is breaded and frozen for sale as a "tail". The term is also applied to shrimp and spiny lobster with reference to their meaty tail sections.

Tempura Batter: A light Japanese-style batter that is becoming increasingly popular.

Tempura Batter: A light Japanese-style batter that is becoming increasingly popular.

ton: In international seafood sales, usually refers to a metric ton (2205 lbs.).

tray pack: A seafood packaging form in which a product is prepackaged on a shallow, clear or foam-plastic tray, over wrapped with transparent, plastic film. An absorbent paper pad, covered with plastic to avoid sticking to the product, is sandwiched between the product and the tray to draw off moisture.

trimmed: Finfish on which the fins and tail have been removed.

Tripolyphosphate (also, Sodium Tripoly, STP): A sodium-based additive used to control moisture loss. Often applied at sea to fresh-shucked scallops. Seafood with Tripoly added is referred to as "wet," "dipped," or "treated."

v-cut: A method of removing pinbones by making a V-shaped cut along both sides of the pinbone strip, leaving most of the nape.

watermarked: Describes the darkened, dulled skin of a salmon as it sexually matures and enters freshwater prior to spawning.

wetlock: Wax-coated cardboard used for shipping fish packed on ice.

wheel: Cross-sectional center cut from large species like sharks and swordfish from which steaks are then cut.

whole fish: The complete fish just as it comes from the water, also called landed or round weight.

yield: The percent of meat recoverable from a fish or shellfish.