Shore things: Cockles, clams, whelks and winkles

They are the underappreciated fruits of British waters. And they're ripe for rediscovery, says Sophie Morris

Folkestone is famous for its whelks, so they say. Or the whelks from Folkestone are famous. Whichever it is, for some reason few of us have caught on to eating them. "Whelks can be awful," admits Mark Sargeant, despite the fact they're on the menu at Rocksalt, his Folkestone fish restaurant, "especially if they are overcooked. And they need a lot of help in terms of flavouring. They're a rubbery protein, just like snails, which need plenty of garlic and parsley to taste great."

While Sargeant, formerly Gordon Ramsay's right-hand man and head chef at Claridge's, explains the plight of the whelk, a dish from his upcoming book, My Kind of Cooking, is brought out from the kitchen by head chef Simon Dyer. It's a whelk stir-fry on a bed of crispy noodles, a Chinese-inspired dish with spring onion, coriander, chilli, ginger and pak choi. Plenty of cooks would think nothing of putting together something similar, but they would choose prawns, chicken, beef or tofu over whelks.

"The reason we're not sure about whelks is both a textural and a visual thing," continues Sargeant. "They're also thought of as a poor man's food, though they're a sea snail, just like abalone, which are very expensive, whereas whelks are cheap and they're sustainable."

Eating whelks at Rocksalt, which opened earlier this year and overlooks Folkestone's harbour, is about as sustainable as you can get. Folkestone is one of the few fishing towns where a daily catch is still landed, and the whelks are brought in by local trawlers and boiled across the road.

Whelks are not the only under appreciated mollusc. Cockles and winkles are similarly overlooked, though the tradition for buying them by the pot and eating them cold with a generous sprinkling of salt has never died out on the Kent coastline. A short stroll from Rocksalt is La's Seafood Stall, a family-run business selling cockles and whelks from £1.50 a pot and winkles for £3 a pint.

Most right-on foodies are aware there are sustainability issues about eating fish, even if it is difficult to know which species should be eaten when. Yet we've been slow to catch on to other treasures of the sea which are popular in other countries. In France, platters of fruits de mer come strewn with the tiny, shiny winkles and fat whelks most British diners are too scared to try. We'll pay substantial amounts for prawns that might have been factory farmed in South-east Asia, when there is an abundance of different seafood on our own shores.

The term mollusc describes a huge number of species – around 85,000 - of invertebrate animals, including squid and octopus. Most have a muscular body protected by a shell. Whelks and winkles are gastropods. Clams, mussels and oysters are bivalves. The prized abalone, a huge gastropod, is little known in the UK but is a delicacy across China and Japan that has been overfished to a critical level. Now most are farmed. Still, there are plenty less desirable gastropods left in the sea.

The shores of Folkestone are currently being eased out of a time warp. Rocksalt's wooden walls rise out of the northerly corner of the harbour. A disused viaduct runs south, whose tracks used to bear travellers bound for grand ocean liners. Cheap foreign package deals led to a half-century long lull in Folkestone's fortunes, but a revival is afoot. Sargeant's contribution is his modernisation of the traditional seafood offerings. He has pots of cockles and whelks on the menu, but there is also mussel popcorn at The Smokehouse, his posh fish and chip shop, and a sweetcorn soup with cockle popcorn which, like the whelk stir-fry, is simple enough to make at home. The soup is made from corn, butter and vegetable stock. For the cockle popcorn, mix a little flour and water into a batter and fry in rapeseed oil.

If you're tempted, there is an unfortunate catch. Unless you live near the coast, molluscs are not always easy to buy. Sainsbury's only sells mussels and scallops. Waitrose sells mussels, clams, scallops and oysters. All have seen increased sales this year with British king scallops up 36 per cent and rope-grown Scottish mussels up 31 per cent. Waitrose fish buyer Jeremy Langley puts their popularity down to "cost-conscious consumers looking to create restaurant-style dinners at home".

If your local fishmonger can't do any better, you could turn to an online supplier, such as The Fish Society, whose abundant frozen mollusc selection includes many different types of clams, scallops, mussels, cockles and whelks. Chairman James Smith says that the trouble with molluscs is not one of image alone. They can be a lot of effort to access for small reward. "I can't see winkles going mainstream. Getting the meat out of the shell is too much like hard work. With a whelk, at least you've got a decent amount of meat there."

Even though there are plenty of clams in the UK, they are more expensive than foreign clams because there isn't much of an industry here. Razor clams, says Smith, are very popular at the moment, and he has seen demand grow steadily over the past six to eight years. Even trendier, though technically not molluscs, are goose neck barnacles, or percebes. This delicacy, a meaty claw a few centimetres long, is incredibly dangerous to collect. They cling to the wave-lashed cliffs of Galicia and can fetch up to €200 a kilo.

"But the great unexploited mollusc market is for limpets," says Smith. "They' re everywhere. They've been on sale in Europe for 150 years, and I suspect we will see them here next." The Smelly Alley Fish Company is also keen to push its whelks, winkles and cockles.

Ben Wright, of The Wright Brothers oyster farm and fishery on Cornwall's Helford Estuary, has seen an increasing interest in whelks, winkles and clams following the success of his oyster business. "With the oysters, we used to whinge a lot about people not wanting to eat them. Now I realise that as a supplier you have to put the product out there and show people how to enjoy it. You've got to encourage them to try new things.

"Whelks are cheap as chips and there is little demand for them, but we've had a good harvest because they gather round the oyster cages. The winkles are easy to forage for. You simply go to the beach at low tide and collect them."

Wright can only collect small amounts of these molluscs on the oyster farm, and they find their way to one of his three restaurants pretty sharpish. "A ramekin of warm whelks or winkles in alioli or salt with a glass of sherry is altogether different to the cold, rubbery things we imagine. It could well be time to fall back in love with molluscs."

We're already conducting a long-time love affair with certain molluscs. Mussels might not be to everyone's tastes, but they are cheap and easy to cook and have been on restaurant menus for years. The Rocksalt take on moules marinières uses bacon and Kentish cider. Scallops, too, are very popular. Both are coming into season this month, but there's nothing to stop us extending the embrace to their poor relations.

Best shellers: Molluscs and more

Scallop An expensive but popular bivalve recognisable by its pretty, fan-shaped shell. Very simple to fry and goes well with pork products such as chorizo.

Oyster Typically a love-it-or-hate-it product and also expensive. Native oysters are homegrown and more expensive; rock or Pacific oysters come from warm waters. Add a few drops of shallot vinegar, perhaps lemon or Tabasco, and swallow raw.

Mussel One of the cheapest and most readily eaten molluscs in the UK. If you want an alternative from moules marinières, try steaming with coconut milk, chilli, lime and coriander instead.

Whelk These fat sea snails won't win any prizes in the looks department, but they're cheap and lend themselves well to all sorts of flavours. Cook, shelled, in a stir-fry.

Winkle Periwinkles are the smallest sea snails that we eat. Extract the meat with a toothpick and dip in alioli, mustard or hot butter.

Cockle A type of clam with the distinctive ridged shell you commonly see on British beaches. Steam like other clams or buy shelled and flavour with salt.

Clam There are many types of clam and they can be steamed, just like mussels, in a few minutes. Classic clam dishes are the Italian spaghetti alla vongole and the Portuguese cataplana, a type of stew of clams with other fish, pork and chorizo.