Microcracks in the shells of eggs pose a major food safety concern to consumers. Research has shown that cracked eggs are more likely to harbor bacteria, including foodborne pathogens. A new technology—called the “modified-pressure imaging system”—combines negative pressure with imaging and can accurately detect almost 100 percent of cracked eggs.
The device, developed by Agricultural Research Service scientists in Athens, Georgia, was discussed in detail in “A Better Way To Spot Eggshell Cracks,” Agricultural Research, February 2009. It uses a negative-pressure chamber to essentially pull the eggshell outward very gently to clearly show any microcracks present in the shell.
The next step was to see whether quality suffered after eggs were subjected to the device.
Food technologist Deana Jones, research leader Kurt Lawrence, engineer Seung-Chul Yoon, and hyperspectral image specialist Gerald Heitschmidt, in the Egg Safety and Quality Research Unit, conducted a study to determine whether exposure to the modified-pressure imaging system had any effect on egg quality during storage.
“After 5 weeks of refrigerated storage, only a slight difference in the amount of water in the whole egg was noted between imaged and nonimaged eggs,” says Jones. “All other quality attributes were the same for imaged and nonimaged eggs.”
These other quality attributes include the egg’s weight, albumen (egg white) height, shell strength, vitelline (yolk) membrane strength, and Haugh unit. A Haugh unit—considered by the egg industry as the “gold standard” of interior egg quality—is a mathematical formula that takes into account the egg’s weight and the height of the albumen.
“This information lets us know that the use of the modified-pressure imaging system to detect cracked eggs does not affect egg quality, making it an important tool for enhancing the safety of shell eggs for U.S. retail sale,” says Jones.—By Sharon Durham, Agricultural Research Service Information Staff.
"Egg Quality Preserved After Exposure to Egg Crack Detection Technology" was published in the July 2011 issue of Agricultural Research magazine.