Horse meat has been discovered in some burgers. (Keith Meyers )
A disturbing discovery has led some consumers to wonder "Where's the beef?" in their supermarket burgers. The Food Safety Authority of Ireland said it had discovered horse and pig DNA in burgers sold by grocery stores in Ireland and the United Kingdom, according to reports.
The finding includes a burger sold by global supermarket chain Tesco that contained 29% horse meat, according to the Associated Press.
U.K.-based Tesco -- one of the world's largest food retailers and known in the U.S. under its Fresh & Easy brand -- apologized for the horse meat-laden burger and pulled store brand burgers from groceries in Britain and Ireland, according to AP.
A meat processor in County Monaghan was cited by Ireland's Agriculture Minister Simon Coveney for the horse meat burger find, which Coveney told state broadcaster RTE was "totally unacceptable." Veterinarians had been called to the meat processor and other factories to conduct more tests.
Ireland's national food safety watchdog also said it had found traces of pig DNA in 85% of burger products -- such as beef curry pie and lasagna -- that it had tested in Irish supermarkets during a routine annual check, as well as beef with horse or pig DNA at local Irish chains. And many carried burgers containing both pig and horse DNA.
But most traces were minuscule, such as the 0.1% horse DNA content in one brand of quarter-pounder beef patties. The watchdog says the unusual animal DNA in Ireland's burgers doesn't pose a health threat. A full investigation is underway.
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