While readily available, fantastic to eat and relatively easy to prepare, one important issue to consider with all forms of fresh seafood is that it starts to spoil as soon as it ceases living. While it is impossible to prevent this natural spoilage process, good temperature control and handling can greatly slow down the rate of spoilage and ensure the product is of as good quality as it can possibly be.
To maintain shelf life and quality, seafood should be constantly stored in chilled conditions, via the use of either ice or refrigeration. Even a short amount of time at ambient temperature will affect seafood’s quality and reduce its shelf life, so this should be avoided or kept to an absolute minimum. As with the storage of most other fresh foodstuffs, the lower the storage temperature the better.
Certain fish species, including tuna, mackerel and herring, are also susceptible to the formation of histamine at elevated temperatures, which can cause issues for consumers. For such species, storage at temperatures lower than 4°C is especially important.
Humane handling is an important issue to consider with regards to live shellfish:
âœ¥ They should be handled carefully, do not allow them to dry out and never drop them as this causes physical shock. Ideally, live shellfish should be stored at consistent temperatures, as extreme changes in temperature can cause thermal shock, leading to an increased rate of mortality.
âœ¥ When storing chilled fish in a refrigerator, always cover them with plastic overwrap to prevent any drying out.
Ice can also be used in conjunction with refrigeration to reduce product temperature and maintain shelf life. If using ice, ensure that excess melt water is removed periodically, so that the fish does not stay in contact with any water. However, there are some exceptions and tuna, salmon and smoked fish products should not be directly iced.
âœ¥ As with all foods, cooked and raw seafood should always be stored separately.
If you adopt correct freezing procedures, it is perfectly possible to provide the same eating experience with frozen and thawed seafood as with fresh, chilled fish that has never been frozen. To maintain the integrity of the product, the freezing process should be undertaken as quickly as possible and at as low a temperature as possible. If you freeze a chilled product yourself, it should be good quality and within the range of its noted shelf-life. Frozen products should be clearly labelled and used in date order. Wrap well in protective packaging to avoid exposure to air which can cause freezer burn and damage the product. Check your frozen seafood periodically to ensure it shows no sign of freezer burn – and discard anything that shows signs of damage.
The thawing process should be done using careful control of temperature and not attempted too quickly – overnight in a refrigerator is ideal. Put frozen products on a plate or tray, cover with plastic overwrap and place them in the bottom section of the refrigerator to thaw slowly. Any excess melt water should be removed. When you eventually remove thawed seafood from the refrigerator you can treat it in the same way as chilled fish.
Pan-frying: This is a great method for any whole pan-ready fish, any fillets, portions and also for scallops.
Griddling: Good for suprême portions, where searing the outside produces attractive bar-marks and leaves the centre of the portion more moist and succulent. Perfect for tuna, which should always be served slightly rare in the centre. Good also for whole king prawns, but not a suitable method for thin, flaky fillets.
Grilling: Better suited to whole fish and flaky fillets. Particularly suitable for oil-rich fish such as mackerel and herring and for halved lobsters.
Barbecuing: Suprêmes of meaty game fish are perfect for marinating in citrus, salt, pepper and olive oil and then barbecuing. Whole portion-sized fish such as snapper and bass are also great, as are whole king prawns and langoustines.
Deep frying: This method is good for fillets, goujons, very small round fish (e.g. whitebait) and langoustine tails (scampi). Fish is either coated in flour, egg and breadcrumbs, or dipped in a batter and then fried in hot oil (180°C) until golden. Lighter tempura batters are also becoming popular.
Poaching: A delicate method suitable for both whole fish and portions, which can be poached in various liquids including lightly salted water, fish stock and wine. Smoked haddock is especially good poached in milk. After poaching, the liquors can be used as the base of a sauce.
Mi-Cuit: A variation on poaching/deep frying is a technique known as Mi-Cuit, where portions of oil-rich fish (ideally salmon) are lightly salted, then immersed and slowly semi-cooked in a flavoured olive oil or duck fat at a constant 48°C. A 60g portion needs 11 minutes, at which point it will have a unique colour and texture. The oil must be discarded after cooking, which makes this a costly method but the result is unique.
Steaming: Perhaps the healthiest way to cook fish and widely used in many aspects of South East Asian cuisine. Simply place portions or whole fish in a steamer over 2–3cm of boiling water. Whole fish can be stuffed with herbs and is also good with aromatic flavours added around the fish or marinated beforehand. Scallops are good for steaming this way. Another method is to fill the base of a large pan with seaweed, add enough water or wine to create steam (but not cover the fish), place portions or whole fish on top, cover with a lid and steam over a medium to high heat. Mussels and other molluscs are also best steamed in the same way but without the seaweed. Fish can also be steamed in a microwave, but the portions must be of even thickness.
Baking and roasting: Since fish is easy to overcook, oven cooking should be used carefully. Whole fish and pavés are best for roasting, particularly oil-rich species. Here are four different methods for baking fish:
Foil wrapping: Fillets, portions and whole fish can be wrapped in foil with a little liquid to create the steam, which cooks the fish.
En papillote: The same principle as using foil but adding greaseproof paper to create individual portion sized ‘parcels’ which are served to the table, adding an element of ‘theatre’ to the dining experience, as the parcels are opened and steam bursts out.
Baking in salt: Whole fish can be placed on a layer of sea salt on a tray, with further sea salt packed around and coating the fish. This is sprayed with water which creates a thick crust when cooked (a 500g fish requires 25 minutes at 200°C). Once cooked, break the crust and gently pull away from the fish without damaging the skin. The fish is then filleted and served. This technique brings out the flavour of the fish and is ideal with sea bass and sea breams.
En croute: Fillets or portions wrapped in pastry, usually with a sauce or filling. Can be individual parcels or made in a multiportion size such as with ‘koulibiac’ – the traditional Russian ‘salmon Wellington’ made with rice, hardboiled eggs and mushrooms.
Boiling: Shellfish such as lobster and crabs can be boiled, but this method is not recommended for finfish.