Horse DNA was found in a significant number of beef burger products tested by the Food Safety Authority of Ireland.
An authority spokesman says there is no clear explanation at this time for the presence of horse DNA in the products tested.
Of the 10 burger products that tested positive for horse DNA, all but one were at low levels, but one was found to be 29 per cent horse meat, relative to its beef content.
It this week published the findings of its targeted study examining the authenticity of a number of beef burger, beef meal and salami products available from retail outlets in Ireland.
The study tested for the presence of horse and pig DNA.
A total of 27 beef burger products were analysed, with 37% – 10 of the 27 products – testing positive for horse DNA and 23 (85%) testing positive for pig DNA.
In addition, 31 beef meal products (cottage pie, beef curry pie, lasagne, etc) were analysed, of which 21 were positive for pig DNA and all were negative for horse DNA.
All 19 salami products analysed tested negative for horse DNA. Traces of horse DNA were also detected in batches of raw ingredients, including some imported from The Netherlands and Spain.
The authority said the discovery of horse DNA in some of the beef burger products raised concerns in relation to the traceability of meat ingredients and products entering the food chain.
The beef burger products which tested positive for horse DNA were produced by two processing plants, Liffey Meats and Silvercrest Foods, in Ireland and one plant, Dalepak Hambleton, in the UK.
They were on sale in Tesco, Dunnes Stores, Lidl, Aldi and Iceland.
In nine of the 10 beef burger samples from these retailers, horse DNA was found at very low levels.
However, in one sample from Tesco, the level of horse DNA indicated that horsemeat accounted for about 29 per cent relative to the beef content.
The authority said it was working with the Department of Agriculture, Food and the Marine, and the processing plants and retailers involved.
The retailers have stated that they are removing all implicated batches from sale today. In addition, Silvercrest Foods has informed the authority that it was withdrawing all products from sale and replacing them with new products.
Authority chief executive, Professor Alan Reilly, said while these findings pose no risk to public health, they did raise concerns.
“Whilst, there is a plausible explanation for the presence of pig DNA in these products due to the fact that meat from different animals is processed in the same meat plants, 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 horse meat and, therefore, we do not expect to find it in a burger.
“Likewise, for some religious groups or people who abstain from eating pig meat, the presence of traces of pig DNA is unacceptable. We are working with the meat processing plants and the Department of Agriculture, Fisheries and the Marine to find out how horse DNA could have found its way into these products.”
The authority and its official agencies carry out several surveys and studies each year as part of its proactive monitoring activities. Its product surveys provide a snapshot of the status of products on the market at specific time.
The legal responsibility for placing safe food on the market lies with the food industry and the authority routinely monitors and samples for compliance.
» Full test results (PDF)