Cool-Water Wash For Eggs Can Help Prevent Microbial Contamination.

Using cooler water to wash shell eggs during a second washing can help cool them quicker. This reduces the potential of foodborne pathogen growth both inside the eggs and on the eggshell surface, according to scientists with the Agricultural Research Service (ARS).

Currently, processors who choose to produce eggs that qualify for the USDA quality shield are required to wash them in water that is at least 32 ºC. Furthermore, these eggs are required to be sprayed with a sanitizing rinse at least as warm as the wash-water temperature. To prevent the growth of potential foodborne pathogens associated with eggs, these warm eggs must then be cooled quickly for storage.

To ensure the eggs are safe for human consumption, USDA requires that all shell eggs be stored at 7 °C or lower after processing. That's because Salmonella--the organism most often associated with foodborne disease and eggs--and other bacteria don't grow well at refrigerated temperatures. Getting to the target temperature quickly can make a big difference.

The researchers tested three water-temperature schemes in commercial dual-washer systems: water at 49 ºC for both washers; water at 49°C for the first wash and 23°C for the second; and both washers at 23°C. They found that using a warm temperature in the first washer, followed by a cool temperature in the second one, could provide the greatest benefit in terms of both reduced egg temperature and acceptable microbial levels.

While Salmonella, Campylobacter and Listeria were all detected in shell emulsion and wash-water samples from cool-water washing treatments, none were detected in the egg contents throughout the storage period of eight weeks.

Fuente: Science Daily
http://www.sciencedaily.com/releases/2007/01/070102122528.htm

Aporte: Constanza Vergara