PepsiCo is reverting to its traditional-look logo for Walkers Crisps and reinstating a favourite flavour as part of plans to create a more natural image for the brand.

The relaunch, supported by a £7.5m marketing campaign, is the biggest push for the Walkers brand in the past decade, and designed to tap into the demand for more natural foods, according to Jon Goldstone, vice president of marketing at Walkers. It will coincide with the company's switch to using 100% British potatoes from next month.

The move follows research by Walkers that found 27% of consumers didn't believe that Walkers' standard crisps were made with only potatoes.

"Over the past 60 years, consumers have lost the link between potatoes and a bag of crisps," said Goldstone. "This is worrying, especially as people are looking for more natural foods. We have a fantastic story to tell about our crisps, which is what this relaunch is about."

PepsiCo updated its Walkers packs at the start of 2006 to herald its switch to sunseed oil, but Goldstone said that it was now "dialling back" on the artificial and processed elements of the logo design, which had been introduced to create a more lively and premium image.

Packs will no longer carry gold and will revert to pre-2006 colours. The Walkers typeface is also being made more traditional. Packs will feature a new design, which shows the evolution of a potato into a crisp.

The brand's Worcester Sauce flavour, dropped at the end of 2005, will be brought back to assuage what Goldstone calls a "national outcry" over its banishment. A Cajun Spice variety is being launched for the impulse channels, with Cheddar Cheese, Chilli Spice and Lamb & Mint dropped.

Marketing for the relaunch kicks off in August and includes TV ads fronted by Gary Lineker with the strapline: 'It rains 154 days a year in Great Britain, which is perfect growing weather.'

Walkers will be at events such as the Farnborough International Airshow, with a mobile stand at which visitors can pick a potato that's then made into a bag of crisps to flavour and eat.