Supermarket meat that is labelled as coming from a rare native breed is little more than “mongrel meat”, say breeders who have complained to trading standards officers.

The row over the meat-labelling came after a range of Gloucestershire Old Spot bacon was introduced in Waitrose stores earlier this year.

Breed experts have accused the supermarket of tricking consumers and cashing in on the niche market for rare breed meat. Trading standards officers are investigating the claims.

The bacon on sale is from crossbreed, or mongrel, pigs. It has been produced from meat that is the product of a Gloucester Old Spot boar mating with a commercial sow. The front of the packaging does not make this clear. On the back Waitrose’s reference to “Our free-range Gloucestershire Old Spot sired pigs” suggests that the bacon is not pedigree meat.

Experts point out that the only thing pedigree about the bacon is the price. A 250g (9oz) pack is on sale at £3.99, or £15.96 per kg (0.5lb), compared with £12.50 per kg of dry-cured Gloucestershire Old Spot bacon sold by the Traditional Breeds Meat Marketing Company. Six rashers of standard British unsmoked thick-cut bacon at Waitrose cost £2.99 or £9.97 per kg.

Richard Lutwyche, of the Gloucestershire Old Spots Pig Breeders’ Club, said the labelling was “at best misleading” and added: “It is a bit like getting a Porsche car with a Skoda engine and selling it as a Porsche. Your impression of a Porsche is not going to be enhanced by the experience.”

The matter is now being investigated by enforcement officers at Berkshire County Council, the home authority to Waitrose.

Mr Lutwyche will also raise his concerns at a meeting with Waitrose executives next week, and he will call for honest labelling of the bacon. He said: “We don’t want them taking advantage of the good name we have built for the breed and the eating quality of the meat.”

His efforts are backed by the Rare Breeds Survival Trust. Richard Clarke, its chief executive, said: “A number of supermarkets are now waking up to the fact that native breeds provide real opportunities for new food experiences. It is great that they are, and we acknowledge they may have to crossbreed to produce what is economic and is good to eat. But we think they must be clearer on their packaging that most of the meat is crossbred.”

Waitrose defended its position and said in a statement: “Crossbreeding is strongly rooted in the heritage of British agriculture and provides a way to improve eating quality in a way that is affordable for our customers and commercially viable for the farmers and breeders. We are currently reviewing all our meat labelling and will carefully consider the views of all parties.”

In the 1970s there were 100 Gloucestershire Old Spot breeding sows in Britain; there are now 1,000, because of the reputation for the quality of the meat. Among supporters of the breed are the Princess Royal, the actress Liz Hurley, and Alex James, the Blur bassist turned farmer.

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