But an American company called Microzap says it has developed a technique that will keep the bread mould free for two months.

BBC: Bread that lasts for 60 days could cut food waste

One of the biggest threats to bread is mould.

BBC: Bread that lasts for 60 days could cut food waste

"We treated a slice of bread in the device, we then checked the mould that was in that bread over time against a control, " he explained.

BBC: Bread that lasts for 60 days could cut food waste

Originally designed to kill bacteria such as MRSA and salmonella, the researchers discovered it could kill the mould spores in bread in around 10 seconds.

BBC: Bread that lasts for 60 days could cut food waste