Why Americans refrigerate eggs, while other countries don’t

Visit most U.S. supermarkets or home kitchens and you'll see eggs in a refrigerator --not sitting on the counter in some basket.

Not so in Asia or Europe where eggs are eggs left out to sit unrefrigerated and sold at room temperature. What’s the deal?

Are we needless wasting energy by putting our eggs in the fridge or are other countries using unsanitary practices?

The answer, according to NPR’s The Salt, comes down to how chicken farmers handle eggs from the moment it comes out of the chicken and a difference of opinion on bacteria proliferation.

Americans, Japanese, Australians and Scandinavians wash eggs right after they are laid with soap and hot water. This creates a cleaner shell but also removes a barely-visible protective layer that naturally helps guard the fragile egg interior from harmful environmental factors such as oxygen and bacteria, such as the ones that cause salmonella.

In the U.S., the eggs shells, which are porous, are then sprayed with oil and refrigerated to improve shelf life and guard against contamination.

In the 1970s, the U.S. Department of Agriculture began requiring egg producers to wash their eggs, though many countries banned the practice since it is easy to do it incorrectly. Eggs contaminated by salmonella cause a reported  142,000 illnesses each year, according to the FDA. Many European countries vaccinate their chickens against the virus, which can infect the chicken’s ovaries, according to The Salt, but the practice is not required in the U.S.

So which method is better? Should we leave our chicken alone?

"They're different approaches to basically achieve the same result," Vincent Guyonnet, a poultry veterinarian and scientific adviser to the International Egg Commission, told The Salt.

"We don't have massive [food safety] issues on either side of the Atlantic. Both methods seem to work."

Although eggs do stay fresh longer with refrigeration—50 days versus 21 without-- Guyonnet says consistency is the most important thing to keep in mind.

In countries where refrigeration is costly, the wash-less method may be a more effective means of preservation to avoid a rapid temperature change that creates sweaty, moldy eggs.