It may be some weeks before Cadbury can assess the true extent of the damage this controversy will cause to its business and its reputation as one of the world's best known confectionery brands.

Its fate hinges on whether it will be prosecuted by the food safety authorities - now a looming possibility - and on whether any of the cases of salmonella montevideo so far are linked to the leak at its factory.

"If it was an isolated incident then they have handled it properly and it seems to be of limited significance," said a spokesman for the accountants Ernst & Young.

However, most major brands survive food recalls, which happen every week and rarely attract much public attention. Over the past few days, the Food Standards Agency has overseen recalls of Flora margarine because of an odd taste and Waitrose recalled batches of The Serious Food Company Tiramisu and Champagne and Raspberry Trifle because of possible fragments of glass.