The red lion symbol was reintroduced in January after almost 30 years of non use

The latest development from food technologists at the Sainsbury's supermarket company could lead to a change in that advice.

Alec Kyriakides, a company microbiologist, said the pasteurising process was a commercial secret and refused to give many details about what methods were involved.

However, he confirmed that the process required freshly-laid eggs to be put in a special type of oven.

In the kitchens at Sainsbury's headquarters in London, we cracked open pasteurised eggs and compared them with the standard kind.

The yolks all looked similar. In fact, the only difference was that the white of the heat-treated egg was slightly whiter - less transparent than the regular white eggs.

Mixed welcome

As for taste and smell, there was no difference.

Linda Ward, who heads up the salmonella unit at the Public Health Laboratory Service, told the BBC that anything that reduced salmonella outbreaks must be good news.

However, not everyone was so welcoming towards the prototype pasteurised egg.

Tim Lobstein, co-director of the consumer group, the Food Commission, said he feared it could simply lead to bad egg production methods.

He said it was not the responsibility of retailers to clean up, but the duty of the egg industry to ensure its practices were better in the first place.

The pasteurised eggs are now being consumer tested for Sainsbury's. The company wants to know, for example, if the eggs will make good meringues.

The eggs could be on sale next year - at a higher cost than standard eggs. And, who knows - perhaps the retailer will tempt Edwina Currie to promote its newest product.