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.