There are health benefits to eating fish and seafood on a regular basis, whether it is wild or farmed. Studies show that people who eat seafood at least once per week significantly lower their risk of heart disease and stroke.
Seafoods, like many other foods, are perishable and must be handled properly to avoid spoilage and the possibility of food poisoning. The following tips are designed to help reduce or eliminate these risks.
When you purchase seafood, always buy from a source that maintains high standards and has the required facilities and knowledge to handle fish.
Know the characteristics of quality seafood, and avoid low quality products.
Look: The eyes of finfish should appear bright, clear - almost alive; the gills reddish; the skin moist with shiny, tightly-adhered scales. Fresh fillets have a bright, shiny colour without browning.
Touch: Fresh fish will give slightly, then spring back into shape when gently pressed.
Smell: Fresh fish shouldn't smell fishy. It should have a fresh, ocean smell.
Wrap seafood in plastic wrap or store in an air-tight container. As a general rule, fresh seafood should not be held more than a day or two before being cooked. From a safety point of view, the maximum temperature for perishable food is 4°C. Based on quality and shelf life, it is recommended that seafood be stored between -1 to 2°C.
Disease-producing bacteria thrive at warm temperatures and can live very well on seafood. In the danger zone - between 4°C and 60°C - bacteria can double in numbers every 15 to 30 minutes.
Even though frozen storage for fish can vary from 3 to 10 months, depending on the oil content of the fish, all frozen seafood should be used within a month or two to ensure the best flavour.
Smoked fish is packaged in many ways - frozen, refrigeration with a limited shelf life, and as a stable shelf product. Consumers are encouraged to follow the storage directions on the packaging and to refrigerate any unused product for a short period of time (maximum two days). Signs of quality deterioration and spoilage of smoked fish include discolouration, mold, and an unpleasant odour. Discard the product immediately if there are any signs of spoilage.
Bivalve shellfish (i.e. mussels, clams and oysters) should be routinely "tapped" to ensure they are alive when purchased. When alive, the shellfish will be tightly closed or will close when tapped lightly. Refrigerate live shellfish in well ventilated containers and cover with a damp paper towel or clean cloth.
Poor thawing procedures can also cause rapid bacterial growth on a seafood product. Freezing will not kill bacteria, but only places them in a hibernation state. These microorganisms will reactivate and grow once thawing begins.
Many frozen seafood products, such as fillets and steaks, may be cooked without thawing if additional cooking time is allowed. If you must thaw frozen seafood, use one of two recommended methods:
Proper cooking is important to destroy any parasites or harmful bacteria that may be present. For finfish, allow 10 minutes cooking time for each inch of thickness. Turn the fish over halfway through the cooking time unless it is less than a half-inch thick. Add five minutes to the total cooking time if the fish is wrapped in foil or cooked in a sauce.
Properly cooked fish will flake easily with a fork and should be opaque and firm.
When cooking shell-on bi-valve shellfish (mussels, clams, oysters), note when the shells open and continue boiling for another three to five more minutes. If steamed, cook the opened shellfish for 4 to 9 minutes. Throw away shellfish that do not open during cooking. When cooking shucked oysters (shell-off), boil for at least three minutes, fry for at least 10 minutes at 190°C or bake for 10 minutes at 230°C.
Cooked products (and any other foods) can be re-contaminated through poor handling or storage practices.
Handle and store raw and cooked seafood products separately and thoroughly wash and sanitize knives, containers and cutting boards after handling raw seafood.
If uncooked products such as sushi, cerviche, or cold smoked fish are eaten, good personal hygiene, proper temperature control and safe food handling practices are very important in reducing the risk of foodborne illness. Health Canada has initiated a process to develop policy for minimizing the risk from raw foods of all animal origin (meat, poultry, eggs, raw milk cheese, fish and seafood). Click here to learn more.