Washed Vs Unwashed Eggs: How Do They Differ?

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Both an ingredient in many recipes and a meal or snack in their own right, eggs are arguably one of the most popular items in kitchen fridges. Eggs are widely regarded at the perfect protein, and they're sold in a wide variety of sizes and colors, but one of the most critical distinctions between the different types is washed versus unwashed.

Before we explore the difference, it's important to understand what's the same about these two types of eggs. From a quality perspective, there's no evidence, including nutritional benefits, of any difference between washed and unwashed eggs. Actual egg differences in terms of quality are affected far more by the laying hen's breed, diet, and living conditions. 

Plus, all commercially produced eggs in the United States, like ones sold at your local supermarket, are required to be washed, regardless of size or color. This has been the case since 1970, when the federal government mandated it. If you're looking for unwashed eggs, you'll need to find a local farm stand or other informal seller, or raise some chickens on your own.

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So why did egg washing become a requirement? It started for a variety of reasons, including the visual appeal of a squeaky-clean egg that's free from debris and other contaminants. However, the primary concern is removing salmonella bacteria, which can be passed either from the mother hen or picked up from the environment after the egg is laid.

Still, it's vital not to "over wash." Health authorities recommend against rewashing eggs bought at the store because, when done improperly, it can actually increase contamination risks for the egg. Commercial washing procedures use tested substances and safe temperatures to prevent the potential for contamination.

One critical difference between washed eggs and unwashed is that the former require refrigeration. Without the protective "bloom," the porous egg shell could let in bacteria that proliferates at room temperature. Also, one of the more common false egg facts is that you need to store your refrigerated eggs on the door: You don't. In fact, they're best kept in the back part of the fridge, where temperatures are more stable.

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Along with skipping a step in the production process, unwashed eggs also provide other benefits. They don't have to be refrigerated and they also typically last longer, too. Unwashed eggs can be stored at ambient temperatures as high as the mid-70s for up to two weeks. But if you do decide to keep them cool in the fridge, you can extend the shelf life to 12 weeks.

Travel abroad and you will typically have a far easier time finding unwashed eggs. Most European and Asian countries don't wash eggs, in part due to issues related to improper washing techniques in previous generations. Still, that's not to say European producers ignore the threat of salmonella; rather, egg-laying hens are often vaccinated to prevent it. In other parts of the world, unwashed eggs are a matter of practicality, as it's difficult or impossible to maintain proper refrigeration temperatures from the point of washing to the point the eggs are consumed.

If you're concerned with potential contamination from unwashed eggs, you can wash them with warm water, unscented soap, and a gentle sanitizing solution. By waiting to do this until shortly before use, you can enjoy both the storage benefits of unwashed eggs alongside the cleanliness of washed ones. Even so, whether you need to wash farmer's market eggs is a matter of opinion and personal preference.