Birds Eye has hit back at the UK’s Advertising Standards Authority after complaints about the accuracy of two recent posters were upheld by the ad watchdog.

The posters for the frozen food group’s Field Fresh products, which were viewed between 14 March and 2 April, contained text that read: “30% more vitamins than fresh vegetables” and cited a study from 1998.

After four complainants challenged the claim, the ASA began an investigation and ruled that, as the 1998 study only refers to vitamin C, it was not accurate.

The ASA report said: “The ads must not appear again in their current form. We told Birds Eye to ensure that they had substantiation for their future claims. We also told them they should not make comparative nutrition claims between frozen vegetables and fresh vegetables.”

However, Birds Eye have blasted the ruling as “ridiculous” and stands by its claim that frozen vegetables are better for shoppers.

Martin Glenn, CEO of Birds Eye parent company Iglo Group, said: “Our advert simply stated that frozen vegetables contain 30 percent more vitamins than fresh. This is backed by accepted research. However, the ASA ruled that we had misled consumers. We feel that this ruling is ridiculous. We’re just comparing two peas in a pod, the frozen one just happens to be better for you than the other.

“At a time when government is encouraging us to eat five a day, it is frustrating that the ASA is preventing companies like ours from educating consumers on the merits of eating frozen vegetables, which are often a more affordable alternative to fresh.”