Bread that lasts for 2 months 'may help cut food wastage'
An American company has developed a technique that it claims can make bread stay mould-free for 60 days.
The bread is zapped in a sophisticated microwave array which kills the spores that cause the problem.
The company claims this could significantly reduce the amount of wasted bread in the UK alone, which is almost a third of loaves purchased.
The technique can also be used with a wide range of foods including fresh turkey and many fruits and vegetables.
One of the biggest threats to bread is mould. As loaves are usually wrapped in plastic any water in the bread that evaporates from within is trapped and makes the surface moist. This provides excellent growing conditions for Rhizopus stolonifer, the fungus that leads to mould.
At its laboratory on the campus of Texas Tech University in Lubbock, chief executive Don Stull showed off the long, metallic microwave device that resembles an industrial production line.
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.
"We treated a slice of bread in the device, we then checked the mould that was in that bread over time against a control," the Guardian quoted Stull as saying.
"And at 60 days it had the same mould content as it had when it came out of the oven," he said.
According to Stull, the machine the team has built uses much the same technology as found in commercial microwaves but with some important differences.
"We introduce the microwave frequencies in different ways, through a slotted radiator. We get a basically homogeneous signal density in our chamber - in other words, we don't get the hot and cold spots you get in your home microwave," he said.
Stull believes that the technology could impact bread in other ways. He said that bread manufacturers added lots of preservatives to try and fight mould, but then must add extra chemicals to mask the taste of the preservatives.
If bakers were able to use the microwave technology, they would be able to avoid these additives.