'Named and shamed'

Heinz ham sandwich filler - contains 20% ham Bernard Matthews chicken breast - 62% chicken Princes Crab paste - 39% mackerel, 20% cod, 11% crab Knorr Taste Breaks pasta (creamy chicken and herb) contains 1% chicken  Click here to see more products Source: Consumers' Association

The body found that phrases such as "farm fresh", "fat free" and "lite" were often misleading, and it now wants the European Union to impose stricter regulations.

Researchers who examined dozens of pre-packaged found that McVitie's Butter Puffs did not contain butter; Heinz ham sandwich filler contained only 20% ham; and Ocean Spray Pure Juice Cranberry with grape and apple, had more grape in it than cranberry.

Unclear labels

Under current rules, manufacturers do not have to tell customers about all of the ingredients they use.

Consumers' Association Campaign

Nutrition claims should be defined in legislation Crackdown on references to health benefits as a marketing gimmick Information about the origin of ingredients and products to be as comprehensive and specific as possible Consumers need to know if GM derived ingredients have been used, for example, soya oil Provide information about nutrition

For example, Golden Wonder does not list salt or sodium as an ingredient on its prawn cocktail flavour crisps, but Golden Wonder confirmed to researchers that they did contain salt in the flavouring.

Even where guidelines had been issued, manufacturers continued to flout them, the research said.

"Low fat" according to the former Food Advisory Committee, a committee of the Food Standards Agency, should mean that the product has less than 3g of fat per 100g.

But consumers said that they find the term "% fat-free" confusing.

UK food and drink manufacturers rely on the loyalty and trust of their customers and in no way set out to mislead

Food and Drink Federation

Researchers found that products which could be viewed as a healthy option by consumers had high fat contents. For example, Walkers Lites!, a low-fat brand of crisps, still had a 22% fat content.

Sheila McKechnie, director of Consumers' Association, said: "Some manufacturers are getting away with seriously misleading descriptions about the contents of their food products.

"They must stop trying to fool consumers and be more honest about their goods.

"Healthy diets are a very important issue. Food-related disease is a priority and at the moment it is more important than food safety."

But The Food and Drink Federation, a food manufacturers industry body, said that the food industry was already working with the Food Standards Agency to improve food labelling.

Deputy Director General Martin Paterson, said: "UK food and drink manufacturers rely on the loyalty and trust of their customers and in no way set out to mislead.

"They do have to get across as much information to consumers on what can sometimes be a very small space.

"Industry agrees that marketing claims and labelling should be truthful and not misleading."

• Low fat claims