Seafood Technology FAQ - What should I consider when purchasing, storing, and thawing frozen seafood?

The technology of handling seafood has improved tremendously in recent years. Today, consumers can find a wide choice of top-quality and wholesome seafood in the freezer case. Commercially frozen fish has been quickly frozen at its peak. When properly thawed, frozen fish is comparable to fish that was never frozen. Yet there are some important points to keep in mind when purchasing and handling frozen seafood.

Frozen fish and shellfish should be packaged in a close-fitting, moisture-proof package. Select packages from below the load line of the freezer case. Look for packages that still have their original shape and the wrapping intact with no ice visible. Do not allow the package to defrost during transportation. Frozen prepared shellfish, such as crab cakes or breaded shrimp, clams, or oysters should be frozen solid with no signs of freezer burn such as discoloration or drying on the surface and no objectionable odor.

After shopping, immediately store commercially wrapped frozen seafood in your freezer. Store frozen seafood in the coldest part of the freezer and hold at 0° Fahrenheit or preferably colder, as close to -20° Fahrenheit as possible. As with other frozen foods, avoid prolonged storage by planning your purchases, keeping in mind first in, first out. Commercially frozen seafood can be stored in the freezer for up to six months.

Many fish and shellfish are "flash frozen" within hours of harvest, while it might take several days for the same seafood to make it to your supermarket as "fresh." Keep this in mind when deciding to freeze fish at home. Freezing fish at home should be reserved for those times when you end up with more product than you can immediately eat, such as after a fishing trip or if someone cancels out for dinner. Also, freezing fish or shellfish in the home freezer will not improve quality; it only maintains it, at best.

To freeze seafood at home, start with high quality and carefully handled product. Fish should be cleaned first under cold water and then patted dry. Wrap with plastic wrap, excluding as much air as possible. Then overwrap your fish with freezer paper or aluminum foil. There are also specially designed plastic bags for use in the freezer. These may also be used for fish. Carefully seal all packages and label with contents, amount, and date. Place package in the coldest part of the freezer and where the cold air can circulate around them, freezing them quickly

Shellfish such as shucked clams, oysters, or mussels can be frozen in rigid air-tight plastic containers. Be sure the meats are covered with their liquor and there is 1/2-inch space between the liquid and the container lid to allow for expansion. Scallops may be frozen in plastic freezer bags. Be sure to exclude air and seal tightly or pack scallops tightly in covered freezer containers. Shucked shellfish can be stored for three to four months. Most shrimp available in the market has been previously frozen. Be sure shrimp has not been frozen if you plan to freeze it. Refreezing shrimp under non-commercial conditions can significantly affect the flavor and textures, and, in some cases, may make the shrimp, when thawed, unsafe to eat.

It is not always necessary to thaw seafood before cooking, depending on how it will be prepared. If thawing is not necessary, simply double the cooking time. But, if your recipe calls for coating, rolling, or stuffing, or if the fish is in a block, you will need to defrost to facilitate handling.

If you plan ahead, defrost the fish overnight in the refrigerator. This is the best way to thaw fish in order to minimize loss of moisture. A one-pound package will defrost within 24 hours. Never defrost seafood at room temperature or with hot or warm water. You will destroy the flesh. If you forget to take your seafood out of the freezer ahead of time, place it in a sink of cold water or under cold, running water. A one-pound package will defrost in approximately one hour.

You may also use your microwave oven to partially thaw your fish. Use the lowest defrost setting, which is usually 30 percent power and follow the manufacturer's instructions for time based on amount of fish. (One pound of fillets defrosts in approximately five-six minutes.) Test; seafood should feel cool, pliable, and slightly icy. Be careful not to overheat and begin the cooking process.