A source at one major supermarket, which did not wish to be identified, said its sales of Cadbury chocolate had fallen by 25% since the recall at the end of June.
The source said: "It's down to the way it has been handled; people do not trust the brand any more. The week the salmonella story broke there was a huge drop in sales and it has pretty much remained at that level."
Hot weather had had some impact on the popularity of chocolate in general - with Nestlé's sales down about 10% - but the far greater drop-off in Cadbury's sales was a clear indicator of a lack consumer confidence, he added.
A rival supermarket also reported a similar drop in sales of Cadbury chocolate.
Cadbury, however, declined to comment. Next week the company will unveil its interim results. The first week immediately after the recall will be included in the period covered.
Analyst John Haynes of Rensburg Sheppards said the 25% sales dip in the supermarkets should not be a source of undue concern.
"It's a big figure but one thing to think about is the percentage of sales.Something like 60% of Cadbury's profits come from US drinks and it manufactures more than just chocolate. It's a small portion of its business."
He added: "I don't think Cadbury has to do anything for the brand to recover. It has to let time heal."
But John Allert, chief executive of brand consultancy Interbrand, said Cadbury needed to raise its profile by using a broad range of media to rebuild trust in consumers and trade.
"Cadbury will recover, have no doubt," he said. "But they need to be using communications vehicles that are appropriate for delivering a message rather than just brand building.
"Undertaking sponsorship is not going to be as effective as using media such as newspaper advertising, radio and advertorials to regenerate trust."