UK cereal firm Kellogg and food giant Mars Inc have defended themselves against a Which? report that has criticised the content of cereal bars made by the companies.

A number of UK cereal bar manufacturers have come under fire from consumer group Which? in a report that tested cereal bars from manufacturers including Kellogg, Mars and Honey Monster Foods.

The report found all but one of the 30 bars it analysed were high in sugar, with more than half containing over 30% sugar, it noted.

In a statement, Kellogg said it was “confused” as to why anyone would call a Nutri-grain Elevenses snack a cereal bar.

“If you’ve eaten one you know it’s not. It’s a baked bar and looks and eats much more like a muffin or cake. We bake it like a cake and market it as a mid-morning snack. In fact compared to other similar mid morning snacks, it’s one of the choices that has slightly less sugar than the norm.”

The report highlighted Kellogg’s Nutrigrain Elevensies as containing nearly four teaspoons’ worth of sugar (18g), more than was found in a small 150ml can of cola (15.9g) and 20% of the recommended daily allowance.

Similarly, Mars also defended its Tracker Roasted Nut bar. Which? had claimed a third of the bar was “fat”. However, Mars claimed there were “inaccuracies” in the report.

“Tracker bars do not contain hydrogenated fat and haven’t since the end of 2011,” a spokesperson said. “Tracker has a 31-week shelf-life, so it is possible that the Which? researcher bought and did their research on a product manufactured before the end of 2011, but those manufactured today are hydrogenated fat free.

“Although Tracker Roasted Nut does deliver nutritional benefits, and we make a nutritional claim about the product as a source of fibre, we do not make health claims.”