A rapid-cooling process could not only reduce the likelihood of salmonella in eggs but also add weeks to their shelf life, according to research at Purdue University.
Developed by Kevin Keener, a professor of food science, the process turns liquid carbon dioxide into a "snow" that is circulated around the eggs to rapidly lower their temperature. The process stabilizes the egg whites' proteins, keeping them at AA grade for up to 12 weeks, whereas traditional eggs slowly cooled by surrounding air lose that grade in about six weeks.
Research has shown that rapidly cooling eggs using carbon dioxide also increases the activity of lysozyme, an enzyme in egg white that has bactericidal properties.
Rapid cooling could also increase the distribution area for egg producers who currently are restricted by six-week shelf lives.
"You could send eggs by ship anywhere in the world if you could get even eight weeks of shelf life at AA quality. We're seeing 12 weeks," Keener said.