Following last year's bird flu health scares, Bernard Matthews lost 28% of its brand value, according to a survey listing the top 100 brands in the UK.

The brand only just scraped into the top 100, reaching number 97 in the league table for the top 100 grocery brands in the UK by value, a list complied by business consultants Intangible Business.

Cadbury Dairy Milk also slipped down a place to number four. The brand's sales fell to GBP451m (US$774m).

Warburtons made second place for the second year running with GBP583m in sales, while rival bread brand Hovis stood at number six in the list, a drop in place from last year's number five position. Heinz Baked Beanz made number ten, again seeing a drop from last year's position of number nine.

Tuna brand Princes dropped ten places to number 57 as it begins to lose its battle with John West.

Coca-Cola remained the UK's most valuable grocery brand, enjoying sales of GBP1.5bn, Intangible Business said.

Stuart Whitwell, joint managing director of Intangible Business said: "The economic downturn has had a profound effect on the grocery market in 2008 and played straight into the hands of discount retailers.

"If, as expected, major supermarkets bring in more lines of own label products to compete with discount retailers, 2009 will see a fierce battle of brand owners. We have seen examples of this in 2008 with Princes losing out to John West, Coke increasing market share over Pepsi and Warburtons firmly establishing itself as the number one provider of baked goods. This will only get worse."

Kettle Chips was one of the biggest movers with a leap of 20 places to number 75. The crisp maker recorded an increase in brand value of 28% (GBP64m), buoyed in part by its broadened product range following the introduction of more convenient, single packets and is fast becoming a major competitor to its more established rivals Walkers, McCoy's and Pringles.

Mars is 2008's second best performer moving up 18 places to number 53. Constant investment in brand advertising has helped the brand maintain its position.

Six new entrants have appeared in this year's report and include McVitie's Digestives at number 85, Snickers at number 88 and Young's Fresh Fish at number 95.