The Government announced plans to overhaul nutritional guidelines in its Healthy Blueprint for Schools last September.
However, in its subsequent consultation on the public health white paper, and the delivery plan last month, it said it would only consider the introduction of nutrient-based guidelines.
This led to concern from campaigners who warned that nutrient-based guidelines are essential to ensure healthy amounts of nutrients and limit potentially unhealthy substances such as salt.
But Dr Helen Crawley, a member of the Department for Education and Skills committee responsible for considering the guidelines in secondary schools, told Children Now the Government was likely to use Caroline Walker Trust guidelines, widely regarded by nutritionists as the gold standard for nutrient-based guidelines.
Crawley, a trustee of the Caroline Walker Trust, said a recent announcement by education secretary Ruth Kelly that guidelines would be ready for this September had taken the committee by surprise, as the public health delivery plan stated internal consultations would finish in 2006.
As a result, she said, it was widely accepted that the Caroline Walker Trust guidelines, which are to be updated and republished in June, were likely to be adopted since "there's no time to do anything else".
Kevin McKay, vice chair for the National Caterers Association, and group manager for catering at Nottinghamshire County Council, would support the move.
"They're well-known and held in high regard, " he said.
However, he pointed out it would not be compulsory for schools to introduce the guidelines until September 2006 and that secondary schools were unlikely to introduce meals based purely on the guidelines from the autumn term.
"How many pupils eating in secondary schools sit down with a knife and fork? It's a grab and go culture. Many schools have 40-minute sessions because if they're catering for 1,500 pupils they just don't have the resources," he said.
"No one objects to the long-term introduction of the Caroline Walker guidelines, but it's not going to happen overnight."
He added if stricter guidelines were introduced too quickly, children would shun meals, and that schools should introduce healthier food gradually, as one of several "meals of the day" options.
McKay said it was likely the Caroline Walker Trust guidelines would be "tweaked".
