Although none tested positive for horse DNA, some own-brand meatballs were found to contain traces of pork.

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The FSAI tested 27 beef burgers and of that sample, 37% tested positive for traces of horse DNA, while 85% were found to contain traces of pig DNA. The amounts detected were very small, except for one beef burger from Tesco, that was found to contain 29% horsemeat.

BBC: Burgers