Brakes has recalled its branded lasagne after tests found a lasagne product supplied to Whitbread contained equine DNA.
The catering supplier said it had launched an urgent investigation after frozen beef mince it had sourced from Pinnacle Foods for use in the meals tested positive for horse meat.
Whitbread's testing revealed the horse DNA and the hotel and restaurant group informed the Food Standards Agency.
Brakes said that as a result a number of Creative Foods branded lines have now been blocked from sale as a precaution. It has also stopped using Pinnacle Foods as a supplier.
In a statement, Brakes said: "We are very disappointed that we have been badly let down by one of our suppliers. Needless to say we have stopped using them with immediate effect. This should not have happened and we have apologised wholeheartedly to any customers that have been affected. Like so many in the food industry we have been the victim of an apparent fraud and we are determined to work with others in the industry to ensure that this is stamped out."
It added that further DNA testing was underway on all of its branded products containing beef and so far it had received 71 negative results.
Brakes will continue to test all of the products that might be affected and is expected to reveal the results by the end of next week.