Members of the Gloucestershire Old Spot Breeders Club have accused the supermarket of misleading customers by marketing its bacon as Gloucestershire Old Spot (GOS) when the meat is, in fact, the product of GOS boars crossed with commercial sows.
The breeders are concerned that by selling inferior cross-bred meat as GOS, Waitrose will diminish the reputation of a breed that they have worked hard to re-establish.
Secretary of the Gloucester Old Spot Pig Breeders Club, Richard Lutwyche said: "The packs have 'Gloucestershire Old Spot' written on them in large letters, along with information about the breed and its history. It is only when you look carefully that it mentions that they are GOS 'sired' pigs - a term that most of the general public would not understand.
"Our feeling is that this is misleading the public into thinking that this is pure pedigree Old Spot pork, a product which individual breeders have spent the last 20-odd years promoting on the back of its superior eating quality.
"The cross-bred bacon simply does not have the same depth of flavour and taste. If people eat this 'mongrel' meat, believing it is GOS, they might well come away feeling disappointed, which would put them off buying GOS pork in the future."
The Berkshire Breed Society has also complained about Waitrose labelling, claiming that the supermarket's Berkshire rare-breed pork is actually the result of Canadian Berkshire sired boars crossed with commercial sows, making the meat only 25% Berkshire.
Waitrose has denied misleading its customers, insisting that the parentage of the pigs is marked clearly on the labels and adding that its meat-labelling is currently under review.
"Cross breeding 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 with whom we work. We believe this offers a balanced approach to delivering great taste and appropriate fat levels.
"The parentage of our GOS pork is clearly communicated through our labelling, which complies with the Food Labelling Advice and Trading Standards. We are currently reviewing all our meat labelling and will carefully consider the views of all parties."
Waitrose buyers are due to meet with members of the Gloucestershire Old Spot Breeders Club on Wednesday, 2 April, to discuss the matter further.