With sales plunging, the processing firm was trawling round for new ideas to boost the popularity of its pilchards.

But it looked like a tall order to create a fashionable food from a fish most of us usually see staring out at us from a tinful of tomato sauce.

However, the solution was brilliantly simple -- the pilchards were renamed "Cornish sardines."

It turned out to be one of the most astute consumer makeovers since Bib-Label Lithiated Lemon-Lime Soda was renamed 7-Up.

For customers, "sardines" evoked mouthwatering images of the delicious grilled fish they enjoy on Mediterranean holidays. Now, sales are going swimmingly – having increased tenfold.

"Pilchards have a stigma attached – people associate them with tinned fish in tomato sauce, and it's a pretty bad memory," said Marie Howell, director of the Pilchard Works processing company in Newlyn, near Penzance.

"Sardines, on the other hand, make people think of eating them grilled in Mediterranean countries as a delicacy. So calling pilchards Cornish sardines has made people see them in a better light.

"When they're not in tomato sauce, pilchards are actually very tasty -- and they're healthy, sustainable and locally caught. But it's taken the rebranding for them to catch on."

Pilchards and sardines are in fact the same fish. But, traditionally, those more than 6in long are known as pilchards, while smaller fish are called sardines.

A century ago, Cornish fishermen were landing thousands of tons of pilchards a year. But by the Eighties, that had dwindled to almost nothing as tastes changed.

The pilchard -- by now practically worthless -- was regarded as good only for animal feed.

Because the shoals which come to British waters to spawn in the summer and autumn are made up of mature fish, most "sardines" sold here have been imported from Portugal or the Mediterranean -- until now.

Since pilchards became Cornish sardines, catches landed by the 12 boats which specialise in the species have gone from being virtually unsellable to fetching around UKpound 1 per kilo (2.2lb).

They are on sale at around half of Marks & Spencer's stores, either fresh in packs or in a marinade as part of its recipes range.

They are labelled "sardines" – only in the small print are they described as Cornish sardines.

Andrew Mallison, the store chain's seafood specialist, said: "They are actually very good, particularly on barbecues. It's a nice succulent, oily fish, very healthy and suitable for Mediterranean-style cooking." A second pilchard factory in Mevagissey, Cornwall, supplies Waitrose.

Legally, small fish of the species should be sold as sardines and large ones as pilchards.

But the traditional 6in distinction is not specified and trading standards officials say the rebranding is therefore acceptable. Pilchard Works is now applying to the European Commission to have the name Cornish sardines protected in the same way as Parmesan cheese, meaning only suppliers in the county can use it.

In the winter, the company switches from fresh fish to salting and pressing pilchards.

Most are supplied as fillets in oil or brine and sold in British delicatessens, or as whole fish packaged in the same way and sent to Italy as Salacche Inglesi.

FISHY FACTS

-- PILCHARDS grow to around 9in and can live 15 years.

-- THEY feed mainly on plankton and small crustaceans.

-- SPAWNING in the open sea or near the coast, they produce 50,000 to 60,000 eggs.

-- ROMAN galley slaves and medieval soldiers used them as a staple food.

-- SINCE the 16th century, they have been caught, salted and pressed in Cornwall as a preserved fish and usually exported to the Continent.

-- AS early as 1591, Sir Francis Drake was urging Elizabeth I to block the trade, to stop supplying England's enemies abroad with nutritious food.

-- BY the turn of the last century, pilchards were the mainstay of the Cornish fishing industry, with 16,000 tons landed annually in Newlyn alone.

-- ONE shoal of 13 million fish, weighing 1,100 tons, was landed by five trawlers from the port in one night in 1905.

-- BY the Fifties, stocks had almost been wiped out, with catches down to 40 tons a year.

-- TODAY, there are once again vast shoals of pilchard and the fish is not endangered.

-- BRITISH suppliers of tinned pilchards in tomato sauce were driven out of business by cheaper imports from South Africa and South America.

-- THE UK tinned pilchard market is worth around UKpound 12 million a year – about 25 million average-sized 155g cans.

-- THAT means sales average less than half a can per year per person – around 3 per cent of the total tinned fish market.

(c) 2003, Daily Mail and the Financial Mail on Sunday, London. Distributed by Knight Ridder/Tribune Business News.

Pilchards renamed 'Cornish sardines,' become big hit in Britain