No time to make a packed lunch before work? Soon you could make it a year in advance.Scientists have discovered a natural preservative which could spell the end of rotting food.

They have pinpointed the substance which destroys the bacteria that make meat, fish, eggs and dairy products decompose.

The preservative, called bisin, could extend the food’s life for several years – and even work for opened bottles of wine and salad dressing.

The discovery is set to revolutionise the way we shop and reduce the 20million tonnes of food waste thrown out in the UK every year.

Bisin occurs naturally in some types of harmless bacteria. It prevents the growth of lethal bacteria including E-coli, salmonella and listeria.