Investigations are under way to try to find out how beefburgers on sale in British supermarkets came to contain horsemeat.
Tests on burgers sold in Tesco, Lidl, Aldi and Iceland found traces of horse DNA — with horsemeat accounting for 29% of the meat content in Tesco Everday Value Beef Burgers.
Burgers containing horse DNA were also on sale in Tesco, Iceland and Dunnes Stores in the Republic of Ireland.
Tesco’s group technical director, Tim Smith said the company “immediately withdrew from sale all products from the supplier in question” after receiving the test results on Tuesday.
Irish food safety officials, who carried out the tests two months ago, said the meat had come from two processing plants in the Irish Republic — Liffey Meats and Silvercrest Foods — and the Dalepak Hambleton plant in Yorkshire.
Silvercrest and Dalepak both said they had never bought horse product and have launched an investigation into two European suppliers.
Professor Alan Reilly of the Food Standards Authority of Ireland (FSAI) said: “There is no clear explanation at this time for the presence of horse DNA in products emanating from meat plants that do not use horsemeat in their production process.
“In Ireland, it is not in our culture to eat horsemeat, and therefore, we do not expect to find it in a burger.”
Traces of pig DNA were also found in 21 or the 31 beef meal products examined by the FSAI — including cottage pie and lasagne.
“For some religious groups, the presence of traces of pig DNA is unacceptable,” said Professor Reilly.
Iceland said it had withdrawn from the sale the two Iceland brand quarter pounder burgers implicated in the study.
Aldi said only one of its products, the Oakhurst Beef Burgers, which are only on sale in the Republic of Ireland, had been affected — and removed from sale.