In Massachusetts, the start of summer is the signal for many people to think about preparing and eating more fresh seafood, especially digging up some local steamers, boiling up lobster, and preparing clam bakes and clam boils. Throughout the year, the staff of Seafood Inspection Unit of the Division of Food and Drug within the Massachusetts Department of Public Health is on duty to assure the citizens of the Commonwealth that the product that is purchased from the local market or restaurant is a safe product. However, a wise consumer is advised to adhere to the following guidelines when purchasing, storing, handling, and preparing seafood.

  • For people who enjoy recreational fishing and shellfishing, it is important to follow state and local regulations and be aware of health and safety advisories about fishing and harvesting areas.
  • Temperatures are particularly important, especially for people who are out fishing and digging clams. A fish held at 50°F will spoil five times faster than one held at 32°F. A good rule of thumb is that the product shelf life is cut in half by every 10°F increase in temperature. So remember, when going out fishing or clamming, bring along a cooler of ice for the fish and shellfish.
  • Always wash hands thoroughly with hot, soapy water before and after handling raw seafood.

How to Purchase

  • Know your seafood dealer - buy products from approved, reputable licensed stores or markets with evidence of good refrigeration, icing, and sanitation.
  • Never buy swollen, dented cans or containers of fish and seafood.

Fresh Fish

  • Fresh fish should have a mild sea breeze odor. A strong, fishy odor generally is not acceptable.
  • Whole fish should have bright, clear and shiny eyes. Scales should be shiny and cling tightly to the skin. Look for bright pink or red gills.
  • Steaks and fillets should be moist and free of drying or browning around the edges.
  • At the market, make sure that cooked seafood products are not in contact with raw seafood products in the display case.

Frozen Fish

  • Make sure the packages are undamaged and fillets or steak are solidly frozen in the package.
  • Fish should be free of ice crystals and freezer burn (i.e., discoloration or drying.)
  • Avoid packages that are above the frost line in a store's display freezer.

Fresh Shellfish

"Shell on" products such as mussels, clams, and oysters should be purchased alive. Shells of live clams, mussels and oysters may gape naturally, but will close tightly when tapped, indicating that they are alive.

  • Live crabs and lobsters will show some leg movement.
  • Live lobsters will curl their tails tightly beneath them when handled.
  • Freshly shucked oysters and scallops have a fresh odor. A clear, slightly milky or light grey liquid should surround freshly shucked oysters.
  • If in doubt about the source or raw oysters, clams, and mussels, ask seafood market personnel to show you the shipper's tag that accompanies "shell on" products or check the shipper number on the container of shucked oysters.

Frozen Shellfish

  • Be sure that shellfish is packed in close-fitting, moisture-proof containers.
  • Frozen, prepared items such as crab cakes or breaded shrimp should be frozen solid with no sign of freezer burn (i.e., discoloration or drying) and no unpleasant odor.

How to Store and Handle

  • Get seafood home and into the refrigerator as quickly as possible. Do not leave perishable items in hot cars or out in the sun for extended periods, unless packed in ice or in a cooler.
  • Keep seafood products cold to keep them safe. Maintain your refrigerator between 34°F and 40°F and your freezer at 0°F or colder.
  • Store fresh fish in the coldest part of the refrigerator - under the freezer or in the "meat keeper" drawer. If you are not going to use the seafood within one or two days, freeze it. However, do not refreeze previously frozen products.
  • Clams, oysters, and mussels should be refrigerated in containers with clean, damp cloths - not with air-tight lids. Use fresh shellfish within one or two days.
  • Keep frozen fish and shellfish frozen at 0°F and for best quality use them within three to six months. The longer these foods are frozen, the more likely they are to lose flavor, texture, and moisture.
  • Pasteurized products such as crabmeat can be stored up to six months in the refrigerator. Once opened, use within three to five days. (Pasteurized products should not be frozen.)
  • Store canned seafood in a cool, dry place for up to one year.
  • Refrigerate and freeze leftovers immediately in moisture-proof packages or containers.

How to Prepare

  • Thaw frozen seafood slowly to minimize drip loss and protect flavor, aroma, and texture. During thawing, always place the product in drain pans or other containers that prevent build-up of melt water and drippings. The quality of seafood held in water deteriorates rapidly.
  • Defrost frozen seafood in the refrigerator, allowing about one day to defrost. For a quicker defrosting, place the seafood package in a resealable plastic storage bag and immerse in a pan of cold water in the refrigerator for one to two hours per pound of seafood. Another defrosting method is to put the original package in a plastic bag, place it in a pan, and run cold water around it in the sink until thawed. If defrosting the seafood in the microwave, cook the product immediately.
  • Don't leave seafood, raw or cooked, out of the refrigerator for more than two hours, including preparation and serving time.
  • Before cooking, rinse seafood in cold water for several seconds to remove surface bacteria.
  • When marinating fish and shellfish, place marinade and seafood in the refrigerator. Do not marinade at room temperature. After use, discard the marinade.
  • Bacteria lingers in towels, cloths, and sponges used during preparation, so keep them clean. If a dishcloth or sponge is used to clean raw juices from fish or shellfish, do not reuse the dishcloth or sponge - wash it first.
  • Wash counters, utensils, plates, cutting boards and other surfaces touched by raw seafood with hot, soapy water. Rinse thoroughly with clean water. Sanitizers containing phenols, such as Lysol and Pinesol, should never be used on seafood contact surfaces.



  • The 10-minute rule is a good guide to cook fish and applies to baking at 450°F, broiling, grilling, steaming, and poaching only. Measure the fish - whole, steaks, or fillets - at its thickest part. Calculate 10 minutes of cooking time per inch of thickness.
    • Cook a one-inch thick fish steak 5 minutes per side.
    • Pieces of fish that measure one-half inch or less do not need to be turned.
    • Add five minutes to the cooking time if the fish is cooked in foil or sauce. Double the cooking time for frozen fish that has not been defrosted.
  • Fish is done when the flesh is opaque and begins to flake easily. If checking with a thermometer, fish is usually ready when the internal temperature reaches 145°F.


  • Clams, mussels, and oysters in the shell should open when cooking. Remove them as they open and continue cooking until all are done.
  • Shucked shellfish, such as clams, mussels, and oysters become plump and opaque when cooked and ready for eating. The edges of the oysters start to curl.
  • Raw shrimp turn pink and firm when cooked. Depending on size, it takes from three to five minutes to boil or steam one pound of medium-sized shrimp in the shell.
  • Scallops turn milky white or opaque and firm. They take three to four minutes to cook thoroughly depending on size.
  • Submerge fresh lobster in a pot of rapidly boiling water. Allow five to six minutes per pound, starting the timer when the water returns to a boil. A cooked, boiled lobster will turn bright red.

Raw Seafood

Many Massachusetts people love raw seafood - little necks on the half shell, oysters, and sushi. Healthy individuals who choose to eat seafood can minimize risks by -

  • Ensuring that raw clams and oysters come from certified waters. For home consumption, keep raw seafood well refrigerated until time of consumption.

Who Should Avoid Consuming Raw Seafood

There are certain people who should avoid or not eat raw or under-cooked animal proteins, including seafood. These at-risk people include anyone who has a weakened immune system, because the immune system cannot fight bacteria as effectively. These people should not stop eating seafood, but it is strongly recommended that these people eat seafood only in the cooked form.

People who may be considered at-risk include anyone with liver disease, either from viral hepatitis, alcohol over-use, or other causes; diabetes; cancer; kidney disease; long-term steroid use, as for asthma and arthritis; immune disorders, including HIV infection and AIDS; stomach or blood disorders; and hemochromatosis, an iron disorder. For those people who are uncertain of their risk of consuming raw seafood, it is recommend that they should consult with their physicians.

A Final Note

The formula for safe seafood consumption is to preventing spoilage. The formula is very simple: Keep seafood clean, cool, moist, and moving. Handle seafood with care and pay close attention to temperatures and sanitation.


News about Seafood Safety and Consumer Tips, developed by the National Fisheries Institute, Arlington, VA , March 1994.
Seafood Savvy, prepared by the National Fisheries Institute, Arlington, VA. September 1996.
Handle with Care: A Retail Seafood Quality Primer, Alaska Seafood, Bellevue, Washington, 1990.
A Food Service Guide to Seafood Quality, Alaska Seafood Marketing Institute, Juneau, Alaska.Ë

This information is provided by the Food Protection Program within the Department of Public Health.