Rapidly cooling freshly laid eggs could add weeks to their shelf life and reduce risk of illness, according to a Purdue University study conducted by Kevin Keener, professor of food science.
The cooling process, developed by Keener, uses liquid carbon dioxide to stabilize the proteins in egg whites so much that they could be rated AA for 12 weeks — current processes give eggs AA status for up to six weeks. The same technology could also reduce occurrences of Salmonella. "There is no statistical difference in quality between eggs as measured by Haugh units (which measure an egg white's protein quality) just after laying and rapidly cooled eggs at 12 weeks," said Keener. "This rapid-cooling process can provide a significant extension in the shelf life of eggs compared to traditional processing."
According to Keener, one of the applications for the rapid-cooling method is global exporting. "You could send eggs anywhere in the world if you could get even eight weeks of shelf life at AA quality," he said. "Right now, you can't ship eggs anywhere in the world and expect to retain that quality."
Keener said with additional funding he would continue to study the benefits of rapid cooling, including inoculating the inside of shell eggs with Salmonella and examining how other proteins in the whites and yolks of eggs are affected.