McDonald's has sparked an official review of Britain's recommended guidelines for cooking burgers. It says the Chief Medical Officer's advice on temperatures and times - issued in 1998 - is more stringent than the US equivalent.
The chain contacted the Food Standards Agency (FSA) which in turn sought independent scientific advice on burger cooking. McDonald's is referred to only as "an American fast food restaurant chain" in the FSA's papers.
E.coli support group HUSH learned the chain's identity after asking the FSA for it under the Freedom of Information Act.
The FSA last month launched a public consultation on the recommendations it received from a sub-group of the Advisory Committee on the Microbiological Safety of Food.
That ad hoc group concluded that UK advice for cooking burgers should remain unchanged at 70C for two minutes or equivalent.
But the use of lower times and temperature combinations could apply to producers who can prove their final product is safe, the group said.
HUSH co-founder Steve Nash warned that any reduction in cooking times or temperatures would increase the risk of E.coli in the UK.
He said: "In relation to McDonald's - and this would be the same for any other company - what we are trying to decide is whether they are doing it for the benefit of the consumer or for other motives. Will it be easier in a large, busy shop to have less cooking time and more turnover?"
A McDonald's spokeswoman said: "With customer safety in mind we fully comply with the Government's guidelines regarding the safe cooking of meat.
"However, these were last reviewed in 1998 and we felt it reasonable to approach the FSA to review these guidelines to ensure they were up to date."
