Fish is an excellent source of first class protein, and in some fish, a valuable source of fats and fat soluble vitamins such as A and D. They provide an important source of minerals, particularly iodine, and the bones of canned sardines and salmon provide calcium and phosphorus.
Fresh fish should appear bright and clear, with the gills still red.
Frozen fish is often better quality than fresh fish from an open counter, but processed fish often includes variable amounts of water.
The best methods of cooking fish are poaching and steaming, which ensure the maximum nutritional value of the fish, provided the juice from the cooked fish is also eaten. Baking, frying or grilling fish can destroy up to 30% of B vitamins.
Fish should not be cooked in batter, which absorbs too much fat. Moist cooking methods are often the best.
Sole, Plaice, Dab and Flounder are the smaller flat-fish, often cooked whole. Best between May and February. They contain almost no fat and are easily overcooked.
Brill, Halibut, Turbot are larger and cut into steaks, but require a moist cooking method.
Cod, Coley, Haddock, Hake, Pollack, Whiting are white fleshed fish. Their quality is best between June and February. They are best steamed or poached.
Salmon and Trout contain up to 10% fat, depending on the season. They can be fried or grilled, but dry out quickly if overcooked.
Herring, Mackerel and Sardine are the oiliest fish and excellent sources of vitamins D and E. They are best fried or grilled.
Tuna and Swordfish contain up to 5% oils if fresh, but canned tuna contain little oil.
Cartilaginous fish are all good sources of vitamin E and excellent for young children as these fish contain no bones. Ray and Skate are best cooked moist Dogfish and Shark need to be skinned before cooking. The flesh is firmer than most fish and they can be grilled or stewed.
Crustaceans are particularly good source of minerals, especially iron. Lobster and Crab must be eaten very fresh. They should be purchased still alive and killed by dropping into boiling water. The head sac and the intestine need to be removed before cooking, the gills discarded after cooking. Prawns and shrimps should also be eaten as fresh as possible.
Molluscs such as Oysters and Mussels are also excellent sources of minerals. They should be alive when cooked or eaten raw. The safest source is tinned mussels.
Frozen fish should be thawed in a refrigerator rather than at room temperature. Fresh fish should be gutted and cleaned as soon as possible and washed well in cold water and then drained. Skin with large prominent scales should be removed.
The domestic refrigerator is too warm to keep fish fresh. If kept they should be packed in crushed ice for no more than a day or frozen immediately.