How to Safely Clean Fresh Eggs—And Know When It's Best to Leave Them Unwashed

It's crucial to understand when and how to properly wash eggs. While eggs are one of the most versatile ingredients in our kitchens, they can also be carriers of Salmonella, a harmful bacteria that can lead to severe food poisoning. Food safety is paramount, especially given the risks involved in improper handling. That's why it's important to know whether or not you should wash your eggs. We spoke with a food safety expert to understand the right circumstances for washing fresh eggs and why store-bought eggs are different from those straight from the farm.

When is it Appropriate to Wash Eggs?

Eggs from the grocery store always appear pristine. "When was the last time you picked up a carton of eggs that didn't look perfect?" asks Marisa Bunning, a food safety professor and extension specialist. They appear so clean because the USDA mandates that eggs are washed before they hit the shelves. "These eggs undergo a specific cleaning process," Bunning explains. But does that mean you should wash them again?

Should You Wash Eggs Bought from the Store?

Since store-bought eggs are already cleaned before being sold, Bunning advises against washing them again. "Washing these eggs is unnecessary and could even cause issues, especially if they're washed in extremely hot or cold water," Bunning notes. "The eggshell is porous. It’s just extra effort and wasteful of water."

Should You Wash Fresh Eggs from Your Backyard?

Fresh backyard eggs are a different case. If you raise your own chickens or receive eggs from someone who does, the situation changes. "Consumers aren't accustomed to eggs from their own backyard," Bunning remarks. "They're treating them the same way as store-bought eggs, but they’re not quite the same."

Although backyard eggs or eggs from the farmer's market are incredibly fresh, they might still require cleaning. If you’re getting eggs from a backyard chicken keeper who is meticulous about flock care and maintains clean nesting boxes, the eggs may not need washing, according to Bunning. However, this is not always the case. "If the eggs are visibly soiled with straw, debris, or manure, cleaning them becomes necessary," Bunning explains.

How to Properly Wash Fresh Eggs

There are two main techniques for washing farm-fresh eggs: wet-washing and dry-washing. Below, we cover both methods. Regardless of which you choose, always make sure to wash your hands both before and after handling the eggs to minimize the risk of contamination. It's also essential to clean and sanitize any surfaces that the eggs may have come into contact with.

Wet-Washing Technique

Wet washing is an effective way to clean farm-fresh eggs. However, after washing, be sure to either use the eggs immediately or store them in the refrigerator. Bunning suggests using water along with an emery cloth or brush to wash fresh eggs.

• Wash each egg individually under warm to hot running water, ranging from 90-120°F. The water temperature should be at least 20°F higher than the egg to ensure proper cleaning. For newly laid eggs, which are typically around 105°F, use hotter water. Avoid washing eggs with cold water, as it can allow bacteria to penetrate the shell.
• While washing, use an emery cloth or brush to gently clean the eggs. An unscented dish soap can also be used for an extra level of cleanliness.
• During the washing process, eggs should never come into contact with dirt or bacteria, which can enter the egg's porous shell.
• Never leave eggs submerged in standing water, as contaminants can enter the porous shell.
• Once washed, ensure the eggs are thoroughly dried.

Dry-Washing Technique

Alternatively, you can clean eggs using the dry-washing method, which helps preserve the protective bloom. This method also allows you to store the eggs at room temperature, rather than in the fridge. To dry-wash, gently rub the eggs with a brush, emery cloth, or fine sandpaper to remove any dirt or debris.

Ultimately, most of the billions of eggs consumed annually in the U.S. don't require washing. However, it’s essential to know that some of the best eggs do need to be cleaned.

How to Sanitize Eggs

The Center for Food Security & Public Health advises that all eggs should be sanitized, particularly if they appear visibly dirty, to prevent the risk of foodborne illness. To sanitize your backyard eggs, follow these steps:

1. Prepare a solution of 1 tablespoon of bleach per gallon of water.
2. Submerge the eggs fully in the solution, and remove them immediately.
3. Rinse each egg thoroughly with clean water.
4. Use a towel to dry each egg completely.
5. Store the eggs in the refrigerator, ensuring the temperature remains between 35-40°F.

Proper Egg Storage

The way you store your eggs will vary depending on whether they are store-bought or fresh from your backyard chickens.

How to Store Store-Bought Eggs

In the U.S., Bunning recommends refrigerating eggs. Unlike in many European countries, the U.S. typically removes the protective "bloom" from backyard eggs. This bloom is a natural coating that shields the eggs from bacteria. Without it, refrigeration is necessary in the U.S. to help prevent bacterial contamination.

"We keep our eggs for a longer period," Bunning notes. "To me, refrigerating them is the best choice. Think of them like dairy products [except butter, which can stay at room temperature]. You wouldn't leave milk or yogurt out for long, and eggs are the same." Bunning also mentions that egg whites (the leftover portion when only the yolks are used in recipes) can be stored in the fridge for up to four days or frozen for a year.

How to Store Backyard Eggs

Backyard eggs don’t necessarily need refrigeration because the bloom helps preserve their freshness. This is why eggs in Europe are typically not stored in the fridge—they retain their bloom. While Europeans and Americans handle eggs differently, the agricultural methods and regulations in each region also contribute to these varied practices.

"There are significant differences between the two," Bunning explains. "You simply can’t compare them." This is an important point to remember when assessing egg grades, how to store them, and whether or not to wash them. Once the eggs are washed and the protective bloom is removed, refrigeration becomes necessary.

Frequently Asked Questions

• How can eggs become contaminated with Salmonella?

  Salmonella can infect the egg white or yolk if the hen laying the egg is contaminated, during the egg-laying process (since eggs pass through the same canal as the chicken’s feces), or via the pores in the egg’s shell.

• Why should you avoid using cold water to wash eggs?

  If the water used to wash eggs is colder than the eggs themselves, it increases the chances that the wash water will be absorbed into the egg, raising the risk of contamination. (Hotter water causes the egg's interior to expand, which makes it harder for contaminants to enter.)