Your guide to choosing seafood

Australia has some of the highest-quality seafood in the world, with an abundance of diverse species, both wild caught and farmed. As with all fresh food, the supply of fresh seafood is affected by weather and seasons, but with Australia’s good climate, clean environment and the increase in aquaculture, many species are becoming available all year.

According to Roy Palmer, of Seafood Services Australia, in most parts of Australia we could eat three different species of seafood a week, every week, without necessarily eating the same species twice in a year.

Eating a variety of seafood not only encourages seafood biodiversity and sustainability but, as part of a varied diet, has potential health benefits. Fish is high in protein, rich in vitamins and minerals and low in calories and saturated fat but, more importantly, the best source of the nutritionally beneficial omega-3 polyunsaturated fatty acids, the “good fats”.

Seafood contains 10–100 times higher levels of these beneficial fats than beef, chicken or lamb. These important oils must be obtained from our diet as our bodies produce only small quantities. Research suggests they help prevent and treat heart disease, guard against prostate cancer, mitigate rheumatoid arthritis and help to reduce asthma in children. The oilier or fattier varieties of fish tend to contain the higher levels of omega-3, such as mackerel, sardines, Atlantic salmon, ocean run rainbow trout, tuna and herring.

According to research by the CSIRO, cooking does not diminish the high levels of omega-3 oils found in seafood. So, whether it’s cooked, uncooked or processed, we should all be including seafood in our diets two to three times a week.

But how do you know if the seafood you’re buying is fresh? How do you know which fish to buy? How long should it be stored? Let’s go through it step by step.

How to know if it’s fresh

Here’s a quick checklist:

  • All fresh seafood should have a pleasant sea smell but not smell “fishy”.
  • Whether whole fish or cut pieces, such as cutlets, steaks or fillets, all should have firm flesh and a good lustre.
  • Whole fish should have bright eyes that are not sunken. Both eyes should be checked together as fresh fish can sometimes have one cloudy eye if the eye has been covered with ice.
  • Whole fish should have red gills.
  • Fish fillets, steaks and cutlets should have no discolouration or oozing of liquid around the edges.
  • Flesh on fish cutlets should be firmly attached around the bone.
  • Crustaceans such as crabs and prawns should have firm, unbroken shells and no discolouration around the joints.
  • Mollusc shells, such as mussels, should be closed or close when tapped or gently squeezed. Discard any with broken shells.
  • Look for prawns without black spots.

Which do I buy?

Get to know your seafood supplier (fishmonger) who has the expertise to offer seafood advice and cooking suggestions. Remember, a retailer with a good turnover is more likely to have fresh stock. Fish is often cheaper when it’s in more plentiful supply, but also be prepared to experiment with a fish species you might not have tried before.

If in doubt get some advice. FISHline is a free seafood advisory service offered by the Sydney Fish Market. Whether you want to know how to choose fresh fish, get species information or recipe ideas, simply telephone (02) 9004 1122 or go to But remember — some of the information will apply to NSW fisheries. you should also seek information where you live.

A fish by any other name

You might notice when buying seafood that some of the fish names have changed. The Australian Fish Names Standard was recently introduced to encourage all seafood suppliers to use the correct standard fish name. To avoid confusion and allow an easy transition, both old and new names will often be seen on shop labels, along with the blue-and-white Fish Names logo. For more details on fish names go to

How do I store it?

Take an Esky or chiller bag to keep seafood cold from the shop to home or ask your retailer to pack ice with your seafood. Remove any paper wrappers before refrigerating. If necessary, scale, gut and clean fish and put in a covered container before refrigerating, but many fishmongers, including those at the Sydney fish Market, will do this for you. If requesting fillets, ask for the fish to be “dry filleted”.

Keep live crabs in a cool place, such as a laundry tub, covering the container with a damp cloth. Place live molluscs, such as mussels, in a container, cover with a damp cloth and store in the warmest part of the refrigerator, which is usually the crisper (optimum 5ºC). Discard any shells that are already open and don’t close when gently tapped or squeezed.

How long can I keep it?

Fresh fish, squid, cuttlefish and octopus should be used within 2–3 days of purchase. Prawns, crabs, lobsters and mussels should be consumed as soon as possible after purchase.

Can I freeze it?

Yes, but it’s far better in terms of flavour to eat your seafood fresh. Fish, molluscs (such as mussels and squid) and crustaceans can be frozen, but check when buying that they haven’t previously been frozen and thawed. Put cleaned, gutted seafood in a freezer bag, extract as much air as possible, seal, label and date it.

Non-oily fish can be frozen for six months; oily fish, molluscs and crustaceans for three months as long as the freezer operates at -18ºC. If it doesn’t, limit freezing to a month.

The best way to store prawns is in their shells in a plastic container. Cover with unsalted water, seal, date and freeze. The large ice-block insulates the prawns. Always defrost in the refrigerator.

How long should I cook it?

Probably for a shorter time than you think! Cook until the flesh changes from translucent to opaque, but there are two things to remember:

  1. The thicker it is, the lower the temperature should probably be, especially if pan-frying or barbecuing.
  2. Food continues to cook after it’s removed from the heat, so it does not have to be absolutely cooked before you take it off the stove.
  3. The most important thing is not to overcook it. If it’s undercooked you can always put it back, but if it’s overcooked it has gone past its best.

Brigid Treloar is a seafood consultant and cookbook author.

The WellBeing Team

The WellBeing Team

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