More chips? Kitchen staff often feel angry about the menus they serve

So what do those on the front line - the so-called 'dinner ladies' - think about the state of school meals?

Kate Steggles, of Noss Mayo, Devon, resigned from her job as a school cook in February, because she was so appalled with the food being served up.

Powdered onions and cream that expanded in water - it was like something out of Doctor Who Kate Steggles, former school cook

She said children at the school - Newton Ferrers Primary School, near Plymouth - "deserved better" and that it "broke her heart" to give them processed foods from packets.

Mrs Steggles, 40, "broke the rules" by buying real potatoes and carrots from petty cash.

But she said she continually hit brick walls when trying to complain to the private contractor supplying the school's meals about the poor choices on offer.

"I ran my own catering business for 12 years, and went into this school job totally blind. I was so shocked when I went into that kitchen," she told the BBC News website.

"I was so sheltered I didn't even know food like that existed - things like powdered onions and cream that expanded in water - it was like something out of Doctor Who.

"I couldn't even bring myself to taste the food that I was serving, which is pretty bad," she said.

'Jamie is God'

The school has since said talks about improving school meals were under way, and that it had started a kitchen garden to grow produce to be used in its school meals.

Many dinner ladies, including Mrs Steggles, cannot praise Jamie Oliver enough.

School meals became a moral issue for Kate Steggles

"He is God as far as I'm concerned," says Becky White, 30, from Hampshire.

She works as a "midday supervisor" at her six-year-old son's primary school, to which ready-cooked food is delivered via a taxi service.

"The menu is set for the year by the council, so there is no flexibility. We get things like smiley face potato fritters arriving dripping in grease and fried beyond belief," she said.

"My son is on hot dinners through the winter, and I am really unimpressed.

"I would not feed my son that food if I had a choice, but the cold lunches on offer would not satisfy him, he needs something hot when it's cold outside."

Food such as turkey twizzlers, roast dinners made with reconstituted meat and fish fingers are served with three vegetables, none of which are fresh, adds Becky.

Don't just go in there and do photo calls - roll your sleeves up mate Becky White on Tony Blair

"It has been so bad on occasion my colleagues have said to the catering people 'you can't feed the children that', but they were just told there was nothing else."

She called on Tony Blair to go into schools and "get his hands dirty" as a dinner lady.

"Don't just go in there and do photo calls. Roll your sleeves up mate," she added.

But it's not all doom and gloom, says Tonia Carter-Coles, another lunchtime supervisor who works at Chew Magna primary school, near Bristol.

"The food there is very good compared to what I've seen on the TV. It's very balanced, and freshly prepared, and we never see junk food on the menu."

But whatever is on the menu it can still be tough persuading the children to eat, she says.

"Some just won't eat anything. It's different for each child, and we can't force them," said Tonia, 36, who has two children at the school.

"Parents will complain if their child hasn't eaten anything at school, it is obviously upsetting," she added.