[Updated April 30, 2018]
Q: If there is a crack in the shell of an egg, is it still OK to use?
Lynne Ausman, DSc, RD, director of the Master of Nutrition Science and Policy program at Tufts’ Friedman School, answers:
A:“Bacteria associated with food-borne illness (food poisoning), including Salmonella, can enter eggs through cracks in the shells. In a study published in the Journal of the Science of Food and Agriculture, eggs with large cracks in the shells were more likely to contain Salmonella compared to eggs without cracks or only hairline cracks (viewed with the help of light in a process called candling). So, check eggs before purchasing to avoid buying those with obviously cracked shells.
“If eggs crack while transporting them home from the store, the USDA advises breaking any cracked eggs into a clean container. Tightly cover the container and refrigerate it, using the eggs within two days. If eggs crack during hard boiling, they are still safe to consume.
“Keep in mind that even non-cracked eggs may be contaminated with Salmonella. The USDA says the number of eggs affected is quite small but cautions us to always handle eggs safely. That includes only buying refrigerated eggs, putting eggs in the refrigerator as soon as you get home from the store (bacteria multiply quickly at room temperature) and cooking eggs thoroughly, until both the white and yolk are firm.” For more information on egg safety, visit fsis.usda.gov, and search on “shell eggs from farm to table.”
To learn more: Journal of the Science of Food and Agriculture, January 2009