How do I cook and pick a whole crab?

A brown crab gives you two quite different foods: sweet white muscle from the claws and body, and rich, soft brown meat from the shell. Buying it whole is far cheaper than buying it picked, and the picking is fiddly rather than difficult. Set aside forty minutes and a bowl for shell.

Safety

What you'll need

• A large pan the crab fits in comfortably
• Salt — a lot of it
• A heavy knife or crab hammer, and a rolling pin
• A crab pick or the handle of a teaspoon
• Two bowls, for white meat and brown meat

Step by step

1. Buy a heavy, lively crab.It should feel heavy for its size — a light crab has recently moulted and is half water. A live one should move when touched. Cock crabs have larger claws and more white meat; hen crabs are broader in the tail flap and give more brown meat. Around a kilo serves two generously.
2. Sedate before dispatching.Twenty minutes in the freezer, or thirty in an ice slurry, makes the crab torpid. This is now the expected standard of handling rather than an optional kindness. Do not put a fully active crab straight into boiling water.
3. Dispatch, or buy it already cooked.A crab is spiked through two points on the underside — one under the tail flap, one in the mouth notch — with a sharp spike or the tip of a knife. If you would rather not, buy a freshly cooked crab from a fishmonger; the picking is identical and it is a completely reasonable choice.
4. Boil in heavily salted water.Roughly sea strength — about 30g of salt per litre. Bring to a rolling boil, lower the crab in, return to a simmer and cook for about fifteen minutes for the first kilogram and five for each additional 500g. Overcooking makes the white meat stringy.
5. Cool it before picking.Lift it out and leave it upside down to cool so the juices stay in the shell rather than draining out. Room temperature, or cold from the fridge — hot crab is unpickable and burns your fingers.
6. Take the claws and legs off first.Twist each one away from the body where it joins. Crack the claws with the back of a heavy knife or a sharp tap from a rolling pin — you want them fractured, not pulverised, so shell fragments do not go into the meat. Pick each leg segment out with a pick.
7. Separate the body from the shell.Turn it on its back, pull off the tail flap, then push the body section firmly upwards with both thumbs at the point where the legs were. It comes out of the shell in one piece with a crack.
8. Remove the parts you do not eat.Pull off the feathery grey gills attached along the sides of the body — the 'dead man's fingers'. They are not poisonous, just inedible. Find the small hard stomach sac just behind the mouth and lever it out whole with the mouthparts.
9. Get the brown meat out of the shell.Spoon everything soft out of the domed shell into a bowl. It ranges from a dark paste to a creamy pale mass and it is all edible. Push down on the line moulded inside the shell rim to snap off the front lip if you want to serve in the shell.
10. Pick the white meat out of the body.Cut the body in half from front to back and pick out the white meat from the honeycomb of chambers with a pick or a teaspoon handle. This is the slow part and it is worth doing properly — there is as much meat here as in the claws.
11. Check for shell.Spread the white meat thinly on a plate and go over it under a good light with your fingertips. Every batch has a fragment or two, and finding one at the table ruins the effort.

Tips

• One kilogram of live crab gives roughly a third of its weight in meat, split around two-thirds white to one-third brown. Work back from that when deciding how many to buy.
• The Food Standards Agency advises limiting how much brown crab meat you eat, because it accumulates cadmium — the white meat is not affected. Check the FSA's current wording rather than a remembered figure.
• Freeze the picked white meat if you cannot use it in two days. Brown meat freezes less well and is better used at once.
• The shells make an outstanding stock. Roast them for fifteen minutes, then simmer with aromatics for half an hour for a bisque base.
• A crab hammer is unnecessary. The back of a heavy knife and a rolling pin do everything, and both give you more control over how hard you hit.

Common mistakes

• Putting a live crab into boiling water without sedating it — Crabs are recognised in UK law as sentient. Chilling first costs twenty minutes and is the accepted standard. It also produces a better result, because a struggling crab sheds its claws.
• Smashing the claws hard — Shell fragments drive into the meat and you will never get them all out. Fracture the shell with a controlled tap and peel it away.
• Throwing away the brown meat — It is the best part of a brown crab — rich, savoury and the basis of dressed crab, crab pâté and crab on toast. Only discard the gills and the stomach sac.

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