Walkers appears to have finally unlocked the key to selling healthier crisps, as year-on-year sales of its wholegrain snack Sunbites rocketed 74% last month following a brand revamp.

In 2010, PepsiCo pledged to deliver 1.7 billion servings of wholegrain every year by 2012 and has already exceeded this by 200 million servings. Pepsi­Co UK president Richard Evans admitted last year in an interview with The Grocer that he had been frustrated by the failure of the brand to take off. "It has high repeat rates," he said, "but we are struggling to get consumers to sample it."

With annualised value sales of Sunbites hitting £17.9m [Nielsen 4w/e 20 August], consumers had responded to a colourful redesign, refreshed website and a series of ads featuring X Factor ­finalist Rebecca Ferguson, said marketing director Victoria Thomas. The activity had been designed to boost awareness of its "wholesome taste credentials", she added.

"Raising awareness of the great taste of Sunbites has been pivotal to our campaign this year. This has resulted in massive gains in market penetration and a rapid increase in brand perceptions around quality and taste," added Thomas, who tipped the brand to reach £20m by the end of the year.

Walkers launched Sunbites in 2007 in a bid to boost its health credentials. A 25g multipack serve or 28g single serve contains more than a third of the suggested daily intake of wholegrains and 30% less fat than regular crisps.