Nature’s Invisible Shield: The Egg Bloom
Every egg is born with a natural defense called the cuticle, or bloom. This nearly invisible coating seals microscopic pores in the shell, acting as armor against bacteria such as Salmonella.
Washing unprocessed eggs under running water—especially if the water is cooler than the egg—can remove this protective layer. When that happens, bacteria can move from the outside of the shell to the inside. In other words, what feels like cleaning may actually reduce the egg’s natural protection.
Store-Bought Eggs
Handling differs depending on whether eggs are commercially processed.
In many countries, including the U.S., large egg producers wash and sanitize eggs immediately after collection. This removes the natural bloom, but it’s done using controlled processes, warm water, and approved sanitizers. Once sanitized, the eggs are refrigerated to maintain safety.
Key takeaway: If you buy eggs from a typical grocery store, they are already clean. Washing them again at home is unnecessary and could increase the risk of contamination.
