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Eggs: washed or unwashed?

A report by the EU’s food regulator not only indicates that it is moving to recommend that table eggs be washed in the bloc, but also provides insight to the different methods and equipment food plants use to handle procedure.

Eggs are a primary source of human salmonellosis in Europe. Egg-associated infections are mainly caused by Salmonella Enteritidis. The European Food Safety Authority (EFSA) panel found that the evidence from other countries that require egg washing indicates that the procedure might help to prevent food contamination and illnesses in human. However in weighing the advantages and disadvantages of the requirement, the safety regulator says it needs more scientific evidence on whether to recommend that the bloc makes a shift in requirements.

EU regulations require that eggs sold directly to the public, defined as "Grade A", must not be washed or cleaned before or after grading. Producers also cannot chill or treat eggs for preservation. Grade B eggs, the second classification in the EU, may only be used by the food or non-food industries and can be washed or unwashed. Other countries like the US and Sweden require that all eggs be washed prior to being sold, claiming the procedure’s food safety benefits outweigh the disadvantages.

The practice of washing of eggs has been mainly developed to clean dirty eggs in the Grade B classification. Another reason for washing eggs is to improve the hygienic quality of eggs by decreasing the bacterial load on the surface and thereby preventing the infection of the inside. Normally the unwashed egg shell serves as a good barrier to bacterial contamination and provides an array of antimicrobial properties for the egg. Washing may harm the delicate shell, encourage the propagation of crack sites and eventually bacterial contamination.

Scientific data regarding current egg washing practices indicates bacteria are reduced on the surface. However, sanitizing eggs will not prevent egg related diseases caused by microorganisms, such as Salmonella that are already present inside the egg.