An A-Z guide to preparing shellfish

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There are many varieties of clam and they come in vastly differing sizes, including soft-shell clams.

Small clams with hard shells may be served raw, like oysters, or they may be prepared and cooked in the same way as mussels. Allow 12 small clams per person.

Large clams are cooked, shelled and diced or chopped before being added to dishes such as soups, casseroles and sauces.

These small shellfish are usually sold already cooked. If fresh cockles are available, the tightly closed shells should be left in a large bucket of lightly salted water for about 3 hours.

Ensure that the cockles are covered by plenty of water and leave them in a cool place. Change the water every 2–3 hours if leaving the cockles for any longer or use a large container overnight. This process of purging removes sand.

Scrub the shells with a stiff brush, and put them in a large pan with 1 cm/½ in water in the bottom. Cover the pan with a lid and cook over low heat, shaking the pan frequently. As soon as the shells open, remove the cockles from the pan.

Serve the cooked cockles cold, with malt vinegar and brown bread and butter.

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This is usually bought cooked, and has often been dressed by the fishmonger. When buying a fresh crab, make certain that it has two claws and that it is heavy for its size.

The edible parts of a crab are the white meat in the claws and the creamy-brown meat in the body shell. Allow 225–275 g/ 8–10 oz dressed crab per person.

Wash the crab and put it in a large saucepan with plenty of cold water seasoned with 15 ml/ 1 tablespoon lemon juice, a few parsley stalks, 1 bay leaf, a little salt and a few black peppercorns.

Cover the pan with a lid and bring the water slowly to boiling point. Cooking time is short. A 1.15–1.4 kg/2½–3 lb crab, about 20 cm/8 in across the body shell, should be boiled for only 15–20 minutes. Leave the crab to cool in the cooking fluid.

Place the cooked crab on a board and twist off the legs and two large claws. Twist off the crab’s pincers and crack each claw open with a claw cracker, a hammer or the handle of a heavy knife.

Empty the white meat into a bowl and use a skewer or the handle of a teaspoon to scrape all the white meat from the crevices in the claws. Set the small legs aside for garnish or, if they are large, crack them open with a hammer and extract the white meat with a skewer.

Place the crab on its back and firmly pull the body (to which the legs were attached) away from the shell. Remove and discard the greyish-white stomach sac which lies behind the head in the shell, and the grey feathered gills, which are known as ‘dead men’s fingers’.

Using a spoon, gently scrape the soft brown meat from the shell and put it in another bowl until required. Cut the body part in two and pick out the white meat left in the leg sockets.

Using the handle of a knife, tap and trim away the shell edge along the natural dark line round the rim. Scrub the inside of the shell thoroughly under cold water, dry, brush it with oil and set aside.

Finely chop the white meat and season it to taste with salt, black pepper, cayenne and a few drops of white wine vinegar. Mix the brown meat with 15–30 ml/1–2 tablespoons fresh white breadcrumbs and season with salt, freshly ground black pepper, lemon juice and finely chopped parsley.

Place the brown crab meat in the centre of the shell and arrange the white meat on either side.

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These are usually sold ready cooked, but live lobsters can be ordered in advance. The shells are then grey-blue, but turn bright red during cooking.

Fishmongers supply live lobsters with the fierce pincers secured with rubber bands. An average-size lobster will serve two people.

Rinse the lobster under cold running water. Grip it firmly round the body part and drop it into a large pan of boiling salted water. Cover with a lid and bring back to the boil. Simmer over low heat, allowing 20 minutes for a 450 g/1 lb lobster and 30 minutes for a 675 g/1½ lb lobster. Leave to cool.

Twist the claws and pincers off the boiled lobster. Using a hammer, a sturdy nut cracker or a specially designed lobster cracker, break the large claws and carefully extract the meat inside.

Remove the thin membrane from the centre of each claw. The head may be cut off or left on. Place the lobster on a board, back upwards, and split in half along its entire length with a sharp knife.

Open out the two halves and remove the gills, the dark intestinal vein which runs down the tail, and the small stomach sac which lies in the head. The green creamy liver in the head is a delicacy and should not be discarded.

The spawn—or roe—in a female lobster should also be kept; it is bright coral red and contained in the tail. It is usually added to the accompanying sauce.

Extract the meat from the tail, and with a small skewer pick out the meat from the feeler claws or set them aside for a garnish. Wash and polish the empty half shells and put all the meat back in them. Garnish with the claws.

As soon as possible put live mussels into a large bucket of cold salted water and throw away any mussels with open or broken shells. If time allows, sprinkle a little oatmeal or flour into the water and leave the mussels in a cool place for 2–3 hours.

The live mussels will feed on the oatmeal and excrete their dirt. Throw away any mussels that float to the surface. Check with the fishmonger when buying mussels, as the majority are now sold ready purged.

Scrub the shells with a stiff brush to remove all the grit. With a sharp knife, scrape away the beard or seaweed-like strands protruding from each shell, and also scrape off the barnacles growing on the shells.

Rinse the mussels in several changes of cold water to remove any remaining grit. Discard any open or broken shells.

Put the cleaned mussels in a large, heavy-based saucepan containing 1 cm/½ in of water or white wine, chopped parsley and shallots or onions. Cover the pan with a lid and heat until the liquid boils.

Reduce the heat so that the liquid does not boil too rapidly, then steam the mussels for about 5 minutes, shaking the pan occasionally. As soon as the shells open, take the pan off the heat and remove a half shell from each mussel.

Discard any mussels that are still closed. Keep the mussels warm under a dry cloth, and strain the cooking liquid through muslin. Serve with the liquid poured over them.

Oysters must be purchased live and opened just before they are served if they are to be eaten raw. Live oysters have firmly closed shells and they should be kept in the refrigerator until they are used, which should always be on the same day as purchase.

Scrub the tightly closed shells with a stiff brush and scrape them, if necessary, to remove all sand and dirt. Oysters contain a delicately flavoured juice that is served with the raw shellfish or reserved for use in a sauce if the oysters are to be cooked.

To open an oyster, use a strong, shortbladed knife, preferably a proper oyster knife. Protect your hand with a thick cloth; a folded ovenglove is ideal. Hold the oyster in one hand, rounded shell down, over a bowl to catch any juices.

If the oysters are to be served raw, the juices should be kept in the shells. Insert the tip of the oyster knife into the hinge. Twist the knife to prise the shell apart at the hinge and cut the two muscles, which lie above and below the oyster.

Run the knife blade between the shells to open them and lift off the top shell. After opening the shell, loosen the oyster with a knife. Serve the oysters in their shells, lightly seasoned with salt and ground pepper and on a bed of cracked ice.

A full guide to preparing oysters

These small shellfish are available all year round and are usually sold ready-cooked and often shelled.

Frozen uncooked prawns are more readily available than the fresh, live shellfish. Live prawns and shrimps are greybrown in colour, but turn bright pink during cooking.

Drop the live prawns or shrimps into a pan of boiling water, cover with a lid and boil for 5 minutes. Leave prawns and shrimps to cool in the cooking liquid.

To peel cooked prawns and shrimps, hold the shellfish between two fingers, then gently pull off the tail shell and twist off the head. Finally, peel away the soft body shell, with the small crawler claws attached.

Fresh scallops are often sold already opened and cleaned, with the beards and all the intestines removed. Wash and scrub the tightly closed shells of live scallops in cold water.

Place the scallops, rounded shells uppermost, on a baking tray in a preheated oven at 150°C/300°F/gas 2 until the shells open; this will take about 5 minutes.

Once the shells have opened, cut through and remove the hinge muscles, and detach the rounded shells. The scallop, attached to the flat shell, is surrounded by a beard-like fringe which must be scraped off. The black intestinal thread must also be removed.

Slide a sharp knife blade under the scallop and carefully ease off the white flesh with the coral attached. Put the white and orange scallop flesh in a pan of cold water. Bring to the boil, remove any scum from the surface and simmer the scallops for 5–10 minutes, being careful not to overcook them.

These molluscs with snail-like shells resemble each other closely, but winkles are smaller. Both are sold ready-cooked, from stalls at the seaside and in London streets, where they are served cold, with salt, black pepper and vinegar.

Whelks are shelled before they are served, but winkles are left in their shells and they must be extracted with a long pin.

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