The new nutritional regulations for Scottish schools could actually reduce the amount of fruit and vegetables children from disadvantaged backgrounds eat, it has been warned.

Joanne Burns from the Food and Drink Federation - the voice of the UK food and drink industry - told a school food conference yesterday that the biggest challenge for councils in meeting the new rules, due to come into force in Scotland next autumn, was ensuring that school dinners remained “palatable” and that children still wanted to eat them.

Ms Burns emphasised the need for the change and to improve the diet of Scottish children, since one in three Scottish children was obese, almost a third of primary children had evidence of dental decay, and Scots generally eat too much salt and not enough fibre.

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However, she pointed out that products that met the new school food specifications often did not exist and months would have to be spent trialling new recipes.

Speaking at the School Food and Feeding the Mind conference in Edinburgh yesterday, Ms Burns said: “I don’t know if any of you have ever seen a high-fibre panini or ciabatta or sub roll or garlic bread? These products at the moment don’t exist, so it’s a huge challenge to the manufacturing sector.”

For schools, she predicted the biggest challenge would be the “three Ps”: packed lunches, picky eaters and parents. The danger was that children “voted with their feet”, she said, and went out for lunch or “ask mum and dad for a packed lunch”. That would be bad news for council coffers but also potentially for pupils’ diets, she suggested.

Ms Burns added that the decision to ban smoothies and fruit juice could also have “implications for overall intake of fruit and vegetables, especially in some of the lower socio-economic groups”.

She said children who had not been exposed to a wide range of fruit and vegetables might have at least taken “a fruit-based drink or a vegetable-based drink as part of their meal” but that would no longer be an option.

Ms Burns said: “We need to make sure when we are reformulating and making these changes that we are not widening the health inequalities gap. We said earlier adults eat 3.2 portions of fruit and veg a day and kids have 2.8, but kids in lower socioeconomic groups have much, much less so we need to make sure by making these changes we are not broadening that gap because that’s a concern for dietary health in Scotland.

“We are worrying about obesity but here are also a lot of people with poor dietary health and who are malnourished.”

The Scottish government launched new nutritional guidelines for school meals in June.

A Tes Scotland investigation last year revealed schools were being rebuked by inspectors for serving deep-fried food too regularly, using high volumes of processed meat and serving baked goods for breakfast.

The new guidelines are thought to be the first in the UK to set maximum limits for consumption of cancer-causing processed red meat over the course of the school week.

However, a more controversial move was the banning of fruit juices and smoothies in schools. When it was first mooted, Obesity Action Scotland pointed out 150 ml of fruit juice counted towards children’s five-a-day recommended intake of fruit and vegetables.