Horsemeat was eaten in Britain until the 1930s but has remained firmly off the menu ever since - despite the entreaties of Gordon Ramsay.
Five years ago, the French-trained chef said: "I've eaten horse", before extolling its virtues as a nutritious meat packed with protein, iron and Omega 3 fatty acids.
For his TV show, Janet Street-Porter, the Independent on Sunday columnist, barbecued horse at Cheltenham racecourse and dished it up to surprised punters.
She said: "In a world of mad cows, we should be opening our eyes to new types of red meat.”
The British have resolutely stuck to the carnivorous quartet of chicken, beef, lamb and pork.
No British supermarket chain stocks horse (intentionally, at least), perhaps because of the likely response from animal lovers, and only a few restaurants, such as L’escargot Bleu in Edinburgh, serve "viande chevaline". Exoticmeats.co.uk sells horse fillets and burgers alongside alpaca and zebra.
Perhaps unsurprisingly for a people with a passion for racing, the Irish share Britons’ cultural aversion to horse flesh.
Professor Alan Reilly, chief executive of the country’s Food Safety Authority, which is investigating the current incident, said: "In Ireland, it is not in our culture to eat horse meat and therefore we do not expect to find it in a burger.”
Gaynor Bussell, an independent dietitian, pointed out there that there was no nutritional or food safety reason against cooking horse (which has only half the fat of beef), but added: “People find eating some meats unacceptable.”
On the Continent, the French, Belgians and Italians have no such reservations and some 200,000 horses are slaughtered for meat annually in Europe, half in Italy. France, Spain and the Netherlands also have substantial abattoir throughputs.
Animal welfare groups Peta and Humane Society International used the contamination to campaign against all meat-eating.
HSI’s EU director, Dr Joanna Swabe, said: “Here in the UK the consumption of horsemeat causes extreme disquiet, but perhaps consumers [should] think about their food choices and the suffering of all animals reared for human consumption.”