If the word 'nephrops' is meaningless to you, it shouldn't be. Better known as langoustine, or scampi when its rear end is dressed in batter or breadcrumbs, it's the UK's most lucrative seafood - netting the fishing industry £200m a year, 10 times the revenue from cod. Stocks are also in a pretty healthy state, unlike other major European fish stocks - a fact recognised last year by the EU, which raised the quota by 33% .

With d0mestic demand still low, this spells a huge opportunity for seafood suppliers such as Young's.That's why it has embarked on ambitious plans to drive growth and why, heart in hand, I joined the softly spoken fishermen on the Sharon Rose off the Hebridean island of Lewis to find out more about Young's vision for what the fishermen simply call 'prawns'.

The weather-beaten trawler, skippered by Murdo MacDonald, boasts a unique in-boat traceability system called Youngstrace, which the company believes will be key to driving sustainable growth.

At the moment, the trawler, which supplies fish to Young's Stornoway processing plant, is one of the only ones with the system, but Young's hopes that the success of the trial will encourage other fishermen to install it.

The senior Young's staff on board the Sharon Rose with me are quick to highlight the size of the prize.

"We can see big growth ahead," says Mike Mitchell, Young's director of scampi. "It's one of the few fisheries in the UK where research indicates that stocks of langoustine are growing. It is already our most lucrative division."

Though langoustine is already lucrative for Young's, the domestic market remains largely untapped, something Young's is keen to address. In a bid to increase its share of the market, it is investing millions in scampi processing facilities, R&D and NPD. So far, it has rolled out an expanded retail range of frozen wholetail scampi in flavoured breadcrumbs into supermarkets.

It also plans to start supplying more whole fresh langoustine to supermarkets as well as boost its 10% share of all langoustine sold into the foodservice sector that currently makes up the bulk of whole langoustine sales.

"In the context of the strength of the market for prawns, langoustine looks like an unexploited opportunity in the UK," explains Young's deputy chief executive Mike Parker. "Ninety-five per cent of whole langoustine is exported, mainly to France and Spain, where it's normally served in the shell."

Developed with help from researchers at Glasgow University, the Youngstrace system is at the heart of the company's plans to catch better quality, more sustainable langoustine - and boost domestic demand.

Young's boasts that it can provide end-to-end traceability, improve the quality of the fish caught and, in tandem with new net technology, slash the amount of by-catch (fish that has been caught by mistake). This is vital for a sector that catches fish by dragging two huge nets, gaping 120ft across the mouth, along the sea bed.

The Sharon Rose's kit certainly looks impressive. Touchscreen technology allows the skipper to enter the time the boat starts trawling and winding in nets, as well as when the crew starts and stops steaming the catch, while a barcode scanner helps them record details of the day's fishing . The information is then relayed to a server on the shore.

This means the company can see when and where the fish was caught and can guarantee to customers that it is also responsibly caught.

"We always used to tell customers that we never knowingly sold illegally landed fish," says Mitchell. "But I always felt it was a bit of a cop-out. With Youngstrace we can see exactly when and where the fish was caught."

A key aspect of the technology is that it shows Young's how long boats have trawled for and how quickly they wound in their nets .

Research has shown both these factors can affect langoustine quality. The longer it is in the nets, the more stress it experiences, chemically altering its taste from sweet and firm to soft and bitter.

Thanks to the scientists, Young's now knows the best-tasting langoustine have pale yellow rather than bright pink marks on their bellies, and can quickly sort them on the quay. As well as using Youngstrace, MacDonald is the guinea pig for new nets with bigger holes to allow unwanted cod, dogfish and plaice to escape. Scientists are crunching the ­numbers from an experimental trawl conducted earlier to see how much better the new nets are, but the early signs are that they slash by-catch by up to two-thirds. The figures should help Young's obtain Marine Stewardship Council accreditation proving its scampi fisheries are sustainable.

Young's sees the technology as the only way to ensure the quality of its catch and wants to see it on board all boats it buys fish from. It pays for the kit and its installation - not the fishermen.

But it's a bold move to ask independent fishermen to install new equipment and adhere to the strict rules that come with it, says Malcolm Blanthorn, procurement manager for Young's scampi business and architect of Youngstrace.

"I'm not the fishermen's favourite character," he says. "But we won't buy fish from Youngstrace skippers who don't stick to our rules, and we won't hesitate to refuse substandard product."

MacDonald, for one, is a convert and now plans to buy a larger fishing boat for about £250,000 to capitalise on the expected uplift in demand. The potential rewards are there for the taking. Young's pays fishermen about £10-15 /kg for good-sized whole langoustine - 15% above the market rate - and guarantees the price throughout the year, protecting skippers from the vagaries of the market.

It hopes the higher quality will mean it can charge a premium for its product and increase sales into the high-value catering trade.

At present, just 10% of the £15m of langoustine bought each year by Young's goes into restaurants and, of the 50% landed whole, 19 in 20 are exported to France, Italy or Spain.

One of the big issues affecting quality is the size of the langoustine caught. Most of the crustacea netted are small and only the succulent tail is saved to turn into breaded scampi for the domestic market - the rest is thrown back into the sea. Using Youngstrace, however, the company can ensure better quality in the bigger whole langoustine that restaurants and increasingly supermarkets are looking for.

"We're working to demonstrate to foreign buyers that the quality of our fish is higher than competitors', and convince them to pay a premium for it," says Mitchell. "To begin with, even chefs in this country were doubtful, saying the best fish is a live one that they can cook straight from the tank in the restaurant. Then they tasted langoustine shipped in ice from our plant in Stornoway, unstressed by a long trawl and longer journey, and they could taste it was better."

Young's is equally ambitious in its plans for the domestic market and is now focusing its attentions particularly on retail.Young's already sells some own-label whole langoustine through M&S but plans are already well advanced to sell branded ­product in Sainsbury's, Asda and Waitrose.

The black thermoform plastic trays that will hold the product have been designed and the company is now finalising the layout of cardboard sleeves so a launch appears imminent.

"We are passionate about expanding the market and bringing it to supermarket shoppers too, so they can enjoy this fantastic product," says marketing manager Jason Manley. "We had M&S's old head of food, Guy Farrant, up here and took him out on the boat to see how the guys catch prawns. After tasting the day's catch, all he said was, 'I want those, and I want them now'. Three weeks later, the langoustine went into stores."

Like many supermarket buyers before me, I found out it's amazing what you can learn from a boat trip.n