You’ve just gotten home from a long day at the office. You’re hungry, you’re tired, and there’s little in your fridge but acarton of eggs to turn into aquick dinner. But when did you buy them? You can’t remember, and they’re past theexpiration date anyway. You obviously don’t want towaste them—eggs are expensive now. How do you tell if eggs are bad?
The short answer: Crack one open and take a whiff. Smelling your egg is the surest way to know if it’s spoiled. If it smells like sulfur, chuck it. But let’s dive a little deeper:
What is a “bad” egg, really?
First, it’s important to understand the differences between anold egg, arotten egg, and asalmonella-infected egg. Anold egg isn’t necessarily unsafe to eat, but it might not taste as good as afresh egg. Arotten egg is one contaminated by common bacteria; it’ll give off a putrid, sulfurous smell. In most cases, consuming a rotten egg will cause mild digestive issues, at most, compounded by a few days of cramping.
However, when consumed raw, an egg infected with the pathogenic bacteriasalmonella can cause serious illness, particularly to the immuno-compromised. Unfortunately,salmonella is odorless, tasteless, and displays no visual cues when present. The excellent news is thatsalmonella inraw eggs is rare and can be eliminated by cooking. So go ahead and bake with abandon (so long as the egg doesn’t smell).
How to tell if an egg is badafter cracking it:
Clue 1: It gives off an unpleasant odor.
“The best way to tell an egg is bad is by using your nose,” says Anna McGorman, VP of Culinary and Operations at Milk Bar and a 20-year veteran pastry chef. “The tried and true way to know an egg is bad is the smell. If you crack one open and are greeted with an eye-watering hit of sulfur, you know your eggs are no longer fit to eat.”
A fresh egg shouldn’t give off anyaroma. But while asulfuric smell can indicate arotten egg, it’s important to note thateggshells are porous and may pick up other odors from the fridge (like cooked fish or onion dip). These may be unappetizing, but they’re not afood safety concern.
Clue 2: It has a watery consistency or discoloration.
If the egg smells okay, but you’re still unsure, check itsappearance. If either theegg yolk or white is runny, the egg might be a little long in the tooth. If theegg white—scientifically known as the albumen—is pink, green, or iridescent, get rid of it, it’s likely infected with bacteria. You want a solid yellow ororange yolk with a clear or slightly cloudy white (cloudy whites equal superfresh eggs).
How to tell if an egg is badbefore cracking it:
You could try thefloat test….
McGorman abides by thewater test to check foregg freshness. To do it, submerge a whole, uncracked egg in a bowl ofcold water to see if theegg floats. “Floating is bad,” she says, but “if theegg sinks, it’s good to use.” The theory is that air penetrates shells aseggs age. Theair cell inside the shell enlarges and becomes the egg’s own little life raft.
…but is thefloat test even accurate?
For freshness, yes, but there’s no scientific basis to rely on it foregg safety measures. You’ll want to use a float-tested egg immediately anyway;eggshells are absorbent, and soaking one in water will make it prone tobacterial growth (more on that in a minute).
