Shellfish is a general term which includes:

Shrimp are available fresh, frozen, and canned. When buying fresh shrimp, look for:

Fresh, frozen, and canned shrimp can generally be used interchangeably in recipes. It is best to use the form stated in the recipe when:

A general rule of thumb: Raw shrimp in the shell lose one size when peeled and lose another size when cooked; or approximately 1/4 pound each during peeling and cooking. Thus, one pound of raw shrimp will result in 1/2 to 3/4 pound of cleaned, cooked shrimp.

The smaller the shrimp size, the higher the count per pound; the larger the shrimp, the higher the price.

For fresh shrimp, raw shrimp in the shell are the best buy. Shrimp can be cooked before or after peeling and deveining, but the sand vein is easier to remove before cooking.

The varieties of crabs differ according to the region. Crabs vary in weight, from the 1/2 to 2 pound blue crab to the 6 to 20 pound Alaska king crab.

Crabs can be purchased live in the shell or cooked in the shell and sold fresh or frozen. Crab meat may be canned.

Live crabs should have a hard shell* and be:

*Note: Blue crabs shed their hard shells three times a year and become soft-shelled. Their availability is limited to May-August.

Cooked whole crabs should have:

Cooked crab meat is available frozen and canned. The package is labeled by the meat it contains.

Flaked and claw meat are less expensive than lump meat.

The following are equivalent to 1 cup cooked lump crabmeat:

An imitation crab substitute product called surimi is commonly sold in grocery stores as an inexpensive substitute for crab. It has low levels of fat and cholesterol, but it can contain up to eight times the sodium found in raw shellfish due to the added salt and MSG.

Clams and Oysters
Clams and oysters are available live in the shell or shucked. Shucked oysters may be purchased fresh, frozen, canned, or smoked. Shucked clams may be purchased fresh or canned.

When purchasing live oysters and clams, the shells should be tightly closed; if open, they should close when touched. Any shells that do not close should be discarded. Shells should not be cracked, chipped, or broken.

Shucked clams and oysters should be:

The liquid is very flavorful and can be consumed with the raw shellfish or used for adding flavor to cooked dishes.

Clams vary in color from pale to deep orange. Oysters are typically creamy white, but they may also be tinted green, red, brown, or pink. Mussels are light tan to deep orange.

Oysters and clams in the shell are purchased by the dozen; shucked oysters or clams by the pint. The following yields apply:

1 Pint: Yields:
Shucked oysters 24 oysters in the shell
Shucked clams 18 small clams

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Lobsters may be purchased live or steamed in the shell and sold fresh or frozen. Lobster meat may also be canned. Live, northern lobsters from Maine and Massachusetts are graded by size. The following designations are used:

Spiny lobsters do not have the large, heavy claws of northern lobsters; their tails are frozen. Fresh lobsters must be shipped and purchased live; they spoil quickly. Live lobsters should be:

Live lobster may be kept in the refrigerator a few hours, if necessary before cooking. Whole cooked lobster in the shell may be purchased fresh or frozen. Cooked lobster should have a:

Cooked lobster meat can also be purchased canned. Cooked lobster need not be reheated before eating, only thawed if frozen. Lobster tail may be purchased frozen, cooked or uncooked. Uncooked, the shells will be a black-green color.

One 8 ounce tail or a 1 pound whole lobster yields:

Scallops are taken from the large adductor muscle that controls the shell movement of the mollusk. Scallops are available both fresh and frozen, usually with their shells removed. There are two common varieties:

Bay scallops are usually more tender with a sweeter, more delicate taste. They can be used interchangeably in recipes, but the cooking time will vary. Scallops should be rinsed well before using to remove any sand.

When purchasing fresh scallops, check that they:

Shucked scallops should not be standing in liquid or on ice.

How much shellfish to buy?
Live shellfish can be purchased in the seafood section of the grocery store or at a seafood store. Cooked shellfish can be purchased frozen or in the deli or seafood section of the grocery store.

How much shellfish to buy?
Shellfish Quantity (per serving)
Raw shrimp
headless, peeled
headless, unpeeled
1 pound
1/4 pound
1/2 pound
1 1/4 pounds
1/4 pound
1 pound
1/2 pound
Oysters, mussels, or clams
6 oysters
6 small hard-shelled clams
3 large hard-shell clams
18 mussels
18 soft-shell clams
1/4 pound
shucked 3 to 4 ounces

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