Scientists Develop New Method for Egg Safety

WASHINGTONAgricultural Research Service (ARS) researchers at  ARS Eastern Regional Research Center (ERRC) in Wyndmoor, Pa., filed a patent on technology that can further protect pasteurized liquid eggs from food-safety threats that include naturally occurring spoilage bacteria and pathogens such as Salmonella enteritidis, the primary cause of egg-related foodborne illness in the United States.

The technology, called crossflow microfiltration membrane separation (CMF), removes more pathogens than thermal pasteurization does without affecting the eggs ability to foam, coagulate, and emulsify. This means CMF-treated eggs could be safely substituted for pasteurized eggs in products where those characteristics are desired, such as angel food cake and mayonnaise. In a pilot-scale study, CMF was shown to remove about 99.9999 percent of inoculated S. enteritidis from unpasteurized liquid egg whites.

The technology also can be used to remove Bacillus anthracis spores from egg whites. This finding adds to previous work in which ERRC researchers used CMF to remove 99.9999 percent of B. anthracis spores inoculated into fluid milk. Microfiltration also can protect milk from more common bacterial pathogens, potentially extending its shelf life.

Current pasteurization technology is not adequate to remove all pathogens effectively from egg products, said Peggy Tomasula, research leader of the ERRC Dairy Processing and Products Research Unit. Though pasteurization eliminates heat-sensitive pathogens, some heat-resistant microorganisms can survive and spoil liquid egg whites.