When Martin Wishart started out in the restaurant business, he had to make early-morning trips to Leith harbour to secure his supply of fresh langoustine. “They were quite difficult to get hold of in Scotland,” he says. “Demand was such in Europe that they went from the port straight onto a truck bound for Spain or France. You had to move fast.”

Now there is an overabundance of Scotland’s most valuable shellfish. The export market, which accounts for 90% of langoustine sales, is being squeezed by the recession. These days the Michelin-starred chef has a regular supplier who transports them live from Kilbrannan Sound in Argyll to his Edinburgh restaurant.

Since the end of last year, the number of restaurants in Spain, France and Italy buying Scottish shellfish has declined dramatically. Some have closed; others taken langoustine off the menu to save money.

“The situation in Spain is very negative and there are no immediate signs of recovery,” says James Cook, of DR Collin & Sons, a fish merchant based in Eyemouth. “In France, it is not as bad, but we have no idea how long this downturn is going to last.”

The export slump has forced shellfish merchants to look for alternative outlets for the 33,782 tonnes of langoustine landed at Scottish ports each year. Some, like Cook, are focusing on the domestic market. He has opened a fish shop next door to his fish restaurant, Marynka, in Linlithgow, West Lothian, where he hopes to encourage the sale of langoustine.

“We are trying to let people know that this is a top-quality product and not as expensive as they think. We can have them for sale just 24 hours after they were caught,” he says.

Cook believes that Scots need to buy langoustine for the industry’s survival. “We have to react strongly to get through this difficult time,” he says. “We are lucky — not many companies are able to take the product from the sea to the plate like we can. But everybody has to look at new initiatives to stay afloat.”

Langoustine (also known as Norwegian lobster or nephrops norvegicus) is worth more than £104m to the shellfish industry. About a third of the world’s landings are made in Scottish waters. The langoustine catch accounts for 30% of the value of all fish arriving in Scotland from UK vessels, with the best landed between October and January.

Iain MacSween, chairman of Seafood Scotland, the trade organisation, acknowledges the European market has dipped and agrees that building up the home market is vital.

“Part of the problem is the British housewife has lost the culture of being able to handle and cook whole fish,” says MacSween. “They prefer it to come on a tray in a supermarket where you don’t know if it is fish or fowl. Langoustine have heads, claws and tails and are not particularly easy to eat, though they are the most delicious shellfish you can get. But you have to be prepared to use pliers.”

MacSween says that on the Continent, grappling with whole shellfish is common. “You see people devouring the stuff. It is part of the eating culture. Sadly, we are just not prepared to do that. Some companies are looking at ways of making langoustine more consumer-friendly — you can even buy peeled langoustine, where all the hard work has been done for you.”

But doesn’t the price put off people? “If you look at the price of langoustine, it is coming down. But, no, it’s not a £1.99 chicken. It is still relatively expensive compared with other fish, but it’s not something that you are going to eat every other day.”

MacSween points out it is available in some Tesco and Morrisons stores. “It’s a small quantity but it’s a start. We have to build it up,” he says.

Chefs such as Wishart are doing their bit. “It is one of the best ingredients we have,” he says. “I’ve taken langoustine from Scotland to New York and cooked it in restaurants like Daniel Boulud’s. People love it.”

Pupils who sign up for Wishart’s Cook School in Leith are taught the best way to handle the shellfish. “It is not complicated once you’ve been shown. Langoustine tails are really nice just cooked in quite salty water — you cook them only for about 90 seconds. It isn’t that difficult.”

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