Now, Purdue professor Kevin Keener is taking a crack at showing how his method, which involves liquid carbon dioxide, also could increase U.S. egg exports. He is also trying to secure funding to study how salmonella-infected eggs might be affected.
Traditionally, Keener said, it takes seven days for eggs to go from chicken laying temperatures -- around 100 degrees -- to refrigeration.
Using carbon dioxide brings eggs down to 45 degrees in 12 hours, he said, while helping to maintain the strength of the membrane that surrounds the egg yolk, which acts as a barrier for bacteria.
That barrier could be retained for 12 weeks, he said, reducing the rate of bacteria production and resulting in a longer shelf life more suitable for exporting.
During the first quarter of 2012, the U.S. exported 20.89 million table eggs to countries across the world including Canada and Japan, according to the American Egg Board.
Comparatively, egg board reported domestic egg production during April was 6.54 billion table eggs, with Indiana being the fourth largest egg-producing state.
Low levels of exporting mean there is a market for his rapidly cooled healthy eggs with longer shelf lives, Keener said.
“With the current process that’s out there, there’s no consideration or requirement for egg temperature,” Keener said.
Keener said the quick-cooling process could result in 100,000 fewer egg-borne illnesses each year.
Jean Jensen, a Purdue research scientist and lab manager, said the process also would help protect consumers who often don’t think about food bacteria.
“General consumers think once they go to the store and buy it, it’s safe as-is,” Jensen said. “It’s also a matter of handling (food) in the kitchen.”
Keener said his next step is to secure funding for more testing, which could include studying what happens when salmonella is added to eggs.
Although he said egg safety is a concern, it is mostly monitored through testing rules, including those outlined in the USDA’s Egg Safety Action Plan.
Preventative processes still need time to go over easy in the egg safety world, Keener said, because methods such as pasteurization are costly. His method is not.
It would cost about $0.05 per dozen to rapidly cool eggs using carbon dioxide, compared to about $0.40 per dozen to pasteurize them, he said.
“It usually takes some type of an outbreak situation (to gain awareness),” Keener said. “As a food safety expert, I hope it doesn’t come but there needs to be a realization that cooling of eggs is important from a safety perspective.”
From the July 5, 2012, Prepared Foods Daily News