In all of literature there are few food moments as iconic, or as horrifyingly embarrassing, as when 8-year-old Ramona Quimby cracks a hard-boiled egg on top of her head in the middle of lunch, only to discover her mother sent her with a raw egg by mistake. Ramona is left crushed, humiliated, and with a whole raw egg in her hair during the middle of school. Generations of children have been a little suspicious of hard-boiled eggs ever since.
If Ramona Quimby had only known Jacques Pépin's trick for how to identify a hard-boiled egg, she could have been spared all that drama!
According to Food & Wine's Alison Spiegel, Pépin says the trick to making sure a hard-boiled egg is cooked through is to spin it on the countertop. If the egg spins around, the egg is cooked. If the egg wobbles around or won't spin, it's not cooked yet.
The reason for the wobble is that a raw egg is full of liquid, which means it does not have a stable center of gravity, so it won't spin. A hard-boiled egg is solid, so it spins like a top.
I Tried Jacques Pépin's Trick and It Really Works
I'm a total sucker for egg tricks. Learning how to tell if an egg is fresh — put it in water, if it sinks it's good, if it floats it's bad — was a game-changer, and probably saved me a fortune in thrown-away eggs over the years. So I decided to try this one myself, and it really works. When I stood the raw egg up on its end and tried to spin it, it flopped immediately over and wouldn't spin at all.
Then I boiled three eggs for two, five, and 10 minutes and dunked them in ice water after boiling, as Pépin instructs, and tried spinning those.
The 2-minute egg spun better than the raw egg, but still not well. It dropped to the side as soon as I tried to spin it, and it just made a lazy arc instead of spinning in place. When I cracked it open there were about two to three millimeters of cooked egg white on the inside of the shell, but the rest of the egg was completely raw.
The five-minute egg and the 10-minute egg both spun like tops. They even spun up on their ends for a moment before tilting sideways and spinning on their sides.
The five-minute egg was a nice soft-boiled egg, with a set white and a runny yolk. If you served it in an egg cup, it would have been perfect for dipping strips of toast in. The 10-minute egg was hard-boiled and yolk and white were both completely set. So the test would not tell you exactly how far along an egg was cooked, but if you had a refrigerator full of eggs and couldn't remember which were raw and which were boiled, Pépin's spinning trick would let you know which was which.