What you see: A carton of raw eggs left out overnight.
What it is: Eggs that have been stored at a temperature that facilitates bacterial growth.
Eat or toss: This depends on where in the world you are! If you’re in a country like the U.S. that typically refrigerates its eggs, the official advice is to toss, though read on for more nuance. If you’re in a country where eggs are sold and stored at room temperature, go ahead and eat. The difference lies in how the eggs were (or were not) washed before they landed in your kitchen.
Is it safe to eat eggs that have sat out overnight? It depends.
Let’s say you live in Boston. After a crazy, late night, you wake up in your Beacon Hill apartment, looking forward to a breakfast of poached eggs. But when you get to the kitchen you are horrified to discover that your eggs are sitting on the kitchen counter, not in the fridge.
You’re about to pitch them when you remember that lovely bed and breakfast in Europe. They didn’t refrigerate eggs at the Lavender Inn, you recall. In fact, you remember how intrigued you were when you learned that they kept them in a drawer. Perhaps, putting your own eggs in the fridge was just a silly, paranoid, American thing to do, you conclude, and you get out your pan.
This is when I leap out of the computer screen and say — hold on!
Because, while it was perfectly fine and charming for the proprietors of the Lavender Inn to keep their eggs in a drawer, it’s dicier if you live in the U.S. The reason comes down to differences in regulations and processing, even though all countries have the same goal: to prevent the spread of salmonella, that hideous bacteria that that can cause diarrhea, fever and abdominal cramps.
Salmonella can come from the chicken’s reproductive tract and land inside the egg, or it can hitch a ride on the outside via some feces that might have stuck to the egg. Everyone agrees on that. What they don’t agree on is the best way to process our eggs to avoid salmonella infection. The American way gets the eggs cleaner, but removes a protective outer layer, thus making refrigeration more important. In some other countries, eggs aren’t cleaned and, with that protective layer intact, they are deemed safe stored at room temperature.
To wash or not to wash eggs
Eggs emerge from chickens with a natural protective coating, known as the cuticle or bloom. In Europe and other parts of the world, that coating is trusted to block bacteria and keep eggs safe at room temperature. In the United States, however, we’re concerned about other stuff, i.e. fecal matter and dirt, that might have landed on the egg shell, and so we’ve devised something like a car wash for eggs. They get scrubbed, rinsed, sprayed and dried, all at precise specifications tuned to minimize food safety risks.
Yet, there are downsides to this sanitation process. First, if the temperatures aren’t right, the eggs’ pores may absorb some of the dirty water. Another drawback to being squeaky clean is that the eggs lose the natural defense provided by the cuticle and need refrigeration from that point forward. According to the American Egg Board’s Eggcyclopedia, about 10 percent of egg packers try to counteract the loss of the cuticle by coating them in edible mineral oil, but most American packers leave eggs a bit more naked than when they were laid.
A few other factors to consider: Some countries, including the United Kingdom, vaccinate their chickens against salmonella, which further cuts down their risk of the bacteria winding up on the egg. But this vaccination is not typically done in the United States. And while you might think there’s no harm in refrigerating the eggs either way, there is an argument in non-refrigerating countries that unwashed eggs shouldn’t be refrigerated at all because if they were ever removed from the cold environment for long enough, condensation could form and thus invite problematic bacteria to the party.
Gizmodo reports that in some parts of Europe it’s even illegal to use the very egg washing facilities that are required in the United States. One thing that might help explain the difference in approach: Business Insider notes that with more chickens in smaller spaces on many U.S. farms, contamination on the egg’s surface is more likely.
And let’s take a step back for a moment, too–it’s not like every egg is contaminated with salmonella. It’s relatively rare (according to our analysis of U.S. government figures and estimates, just shy of 100,000 Americans likely got salmonella from eggs in 2018). But any egg could be contaminated, which is why it’s important to handle them the best way you can.
So, which countries have it right? It’s hard to know. But the takeaway is that if you live in the U.S., your eggs should live in the fridge. And, of course, no matter where you live, cooking eggs properly is the surest way kill any salmonella that’s somehow survived all this scrubbing, vaccinating, and chilling.
Back to those eggs you forgot to put in the fridge
So, let’s head back to your apartment in Boston. You’re in the U.S. so your eggs should have been refrigerated and have now gone without that cold-temperature protection for at least 12 hours.
The United States Department of Agriculture advises against eating eggs that have been outside of refrigeration for more than two hours. The Canadian government gives similar advice. If that’s enough to convince you to toss the eggs in the compost, then that’s an informed and reasonable choice.
But if you’re looking for justification to eat the eggs, check out this episode of the podcast Risky Or Not. When asked about a carton of eggs left in a car for several days, food safety experts Don Schaffner and Ben Chapman concluded that the eggs would not be risky to eat. Their reasoning was that, if the eggs were relatively fresh and the car was relatively cool, there wouldn’t have been enough time for salmonella to flourish.
We all have to make our own individual risk assessments. No food is perfectly safe, and some are riskier than others. Any time you eat an egg with a runny yolk, you’re taking a risk. (Those same government bodies recommend cooking an egg until the yolks are firm.) If you enjoy raw cookie dough, you’re taking an even greater risk.
Any egg could be carrying salmonella bacteria, though if the circumstances are right, (erm, wrong), an improperly stored egg could be carrying much more of it. Still, experts advise that the bacteria can’t survive at 165 degrees Fahrenheit or after several minutes at 145 degrees Fahrenheit, so a thorough cook could give you some additional peace of mind. Still, as we wrote about in this post which is literally about a rotten egg and this one about a dented, cracked egg, all bets are off if your eggs are compromised.
For more egg questions, check out our Egg Library.
- Bloom – Eggcyclopedia — American Egg Board
- Glossary of Poultry Terms. College of Agriculture, Food and the Environment. University of Kentucky.
- Americans why do you keep refrigerating your eggs?
- Why Europeans don’t refrigerate eggs
- Here’s why we need to refrigerate eggs. Los Angeles Times.
- I left the egg carton on the kitchen counter overnight. Are the eggs safe to use? – Eggsafety.org
- Why the US chills its eggs and most of the world doesn’t – NPR
- Safe Food Handling Tips – IncredibleEgg.org
- U.S. should vaccinate poultry to stop killer salmonella
American eggs are so chill…