Kieran Doherty / Reuters, file

Fast-food chain Burger King has dropped a supplier whose supermarket products were found to contain horse DNA. The restaurant company says its products were not affected.

LONDON — Burger King said on Thursday it had stopped using one of the firms caught up in the scandal of supplying British grocers with hamburger that contained horse meat.

The British food industry has been rocked by the revelation last week that retailers including market leader Tesco and smaller chains Aldi, Lidl and Iceland had sold beef products that contained horse meat.

Food safety experts say horse meat poses no added health risks to consumers, but the discovery has raised concerns about the food supply chain and the ability to trace meat ingredients.

On its website, Burger King said it had decided to replace all Silvercrest products in Britain and Ireland with products from another approved Burger King supplier.

"This is a voluntary and precautionary measure," Burger King said. "We are working diligently to identify suppliers that can produce 100 percent pure Irish and British beef products that meet our high quality standards."

The company said last week it was "confident" its beef supplies had not been affected because its patties are made on a dedicated production line and, unlike products implicated in the horse meat scandal, do not contain meat from continental Europe.

The burger products from the grocers, which were revealed last week to have tested positive for horse DNA, were produced by Liffey Meats and Silvercrest Foods in Ireland and Dalepak Hambleton in Britain.

Tesco, Britain's biggest retailer, immediately withdrew from sale all products from its supplier, Silvercrest. The grocery chain said it was working with authorities and the supplier to urgently understand how horse meat came to be in the product.

ABP Food Group, which owns Silvercrest, said at the time that the source of the contamination was a beef-based product bought from two third-party suppliers outside of Ireland.

The discovery of horse meat could be both embarrassing and damaging for the retailers involved. The mass-selling Sun newspaper carried the Burger King announcement on its front page Thursday with the headline "Shergar King," in reference to a famous racehorse that was kidnapped and never seen again.

Related:

Hamburgers pulled from UK shelves after horse meat discovered

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Darren Staples / Reuters, file

In 2007, celebrity chef Gordon Ramsay called for British people to start eating horse meat, saying it was healthy and "packed with protein."

LONDON — The idea of eating horse meat has been described as the "last taboo" of English cooking.

So one of Britain's leading supermarkets, Tesco, was doubtless horrified at having to post a statement saying that horse DNA had been found in hamburgers on sale in the U.K. and Ireland.

Tim Smith, Tesco’s group technical director, said the store apologized "sincerely for any distress" caused.

"We immediately withdrew from sale all products from the supplier in question," he stressed. "The presence of illegal meat in our products is extremely serious.  Our customers have the right to expect that food they buy is produced to the highest standards."

The discovery was made by the Food Safety Authority of Ireland, which said it had carried out a study to examine the "authenticity" of several beef burger, beef meal and salami products.

The results were alarming. Ten of the 27 beef burgers tested were found to contain horse DNA, with nine containing only "very low levels."

"In one sample from Tesco, the level of horse DNA indicated that horse meat accounted for approximately 29 percent relative to the beef content," the FSAI said.

Twenty-three of the 27 burgers also tested positive for pig DNA, the FSAI said, and 21 out of 31 "beef meal products" tested were also found to contain pig DNA, but no horse DNA was discovered.

'No clear explanation'
The FSAI said that the beef burgers with horse DNA were produced at two processing plants in Ireland and one in the U.K., and were sold at Tesco and four other outlets, Dunnes Stores, Lidl, Aldi and Iceland.

Alan Reilly, the FSAI’s chief executive, said in a statement "there is no clear explanation at this time for the presence of horse DNA in products emanating from meat plants that do not use horse meat 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," he noted.

"Likewise, for some religious groups or people who abstain from eating pig meat, the presence of traces of pig DNA is unacceptable," he added.

Reilly stressed the products did "not pose any food safety risk and consumers should not be worried."

In 2007, celebrity chef Gordon Ramsay called for British people to start eating horse meat, saying it was healthy and "packed with protein" with a "slightly gamey" flavor, The Telegraph newspaper reported. The idea failed to take off.

In Britain, two consumers largely spoke for the nation when they told ITV News of their shock and horror.

"I'd be fuming if I found out there was horse meat in my burgers -- obviously," one man said.

"It's just not normal," a woman added. "Fine we eat cows and everything, but horse meat? No."

Jessica Stark, director of communications for World Horse Welfare, said that campaign group was concerned about horses in Europe who are driven to be slaughtered in journeys that can last several days. She said WHW did not oppose the eating of horses, but wanted to see journey times restricted to nine to 12 hours.

She said in some countries horses were seen as companions or pets and were "revered," while other nations, such as Italy and France, saw them simply as livestock.

Asked if she had eaten horse, Stark said "Gosh, no, not that I'm aware of." Asked if she would, she replied, "No I would not ... it's a personal choice."