Should You Wash Eggs Before Using?
In the US, do not wash store-bought eggs - they have already been washed and sanitized, and additional washing can push bacteria through the shell. Store them refrigerated. In Europe and many other countries, eggs are unwashed and unrefrigerated but have natural protective coatings. If you have farm-fresh unwashed eggs, wash them just before use, not before storage.
Key Takeaways
- US regulations require commercial eggs to be washed and sanitized before sale.
- Visibly dirty eggs should be gently cleaned or discarded, not cracked with debris on the shell.
- Once refrigerated, eggs should stay refrigerated - temperature changes cause condensation that can help bacteria enter.
Explanation
US regulations require commercial eggs to be washed and sanitized before sale. This removes the natural protective coating (bloom or cuticle) that seals the porous shell. Without this coating, eggs must be refrigerated to prevent bacteria from entering. Washing them again at home can force bacteria through the now-unprotected shell into the egg.
European eggs are not washed, preserving the natural bloom that prevents bacteria from entering. These eggs can be stored at room temperature. Different food safety philosophies: the US washes eggs and vaccinates chickens less; Europe vaccinates chickens more and keeps the natural shell protection.
For farm-fresh or backyard eggs that have not been washed: store them unwashed and unrefrigerated if you will use them soon, or refrigerate for longer storage. Wash just before cracking to avoid pushing any surface contamination through the shell. Use warm water (not cold, which can create suction) and dry immediately.
Egg shell porosity is the key factor in all egg washing decisions. A chicken egg shell contains approximately 7,000-17,000 tiny pores that allow gas exchange during embryo development. The natural bloom seals most of these pores with a thin protein layer deposited during laying. When this bloom is washed away (as in US commercial processing), the exposed pores become entry points for bacteria, moisture loss, and odor absorption, which is why washed eggs must be refrigerated at 40°F or below.
Farm-fresh unwashed eggs with intact bloom can safely sit at room temperature for 2-3 weeks in moderate climates. Refrigerated unwashed eggs can last 3-6 months because the cold slows all biological processes while the bloom continues to protect. When you do wash farm eggs before use, the water temperature should be at least 20°F warmer than the egg (ideally 110-120°F) to prevent thermal contraction that pulls bacteria inward through the pores. A quick rinse under running warm water is sufficient - soaking eggs is never recommended.
Things to Know
- Visibly dirty eggs should be gently cleaned or discarded, not cracked with debris on the shell.
- Once refrigerated, eggs should stay refrigerated - temperature changes cause condensation that can help bacteria enter.
- Egg carton dates are usually 'sell by' dates; eggs are typically good for 3-5 weeks after purchase.