Queasy consumers in Britain and Ireland are chucking out frozen hamburgers after learning that they could contain horse meat. Food safety experts conducting DNA tests found that around a third of burgers from major supermarket chains contained horse DNA, the Telegraph reports. The levels of horse DNA were fairly low in most samples, but one burger product from Tesco was found to be 29% horse meat, which is legal to sell in both countries but is not commonly eaten.
Pig DNA was also found in a majority of beef burger products and in other processed foods containing beef. "In Ireland, it is not in our culture to eat horse meat and therefore, we do not expect to find it in a burger," says the chief of Ireland's food safety authority. "Likewise, for some religious groups or people who abstain from eating pig meat, the presence of traces of pig DNA is unacceptable." Officials say that while the presence of pig DNA could be because pork is processed in the same plants as beef, the horse DNA is a mystery. (Read more horse meat stories.)