You put two eggs in a bowl full of water. One stays at the surface, it floats; the other one sinks to the bottom like an anvil.
“What to do ?”, you might ask. Well, it’s very simple ! Gently pick up the egg that floats and throw it in the bin (or serve it to your worst enemy). Now, roll up your sleeve, plunge your hand into the water and recover the other egg.
Next, prepare to your liking this egg unfit for flotation. It is good for consumption. Boiled, scrambled or poached, enjoy it without hesitation. If it sank, it’s because it is all fresh !
Boiled fresh eggs
The air cell of an egg
It must be said that an egg that floats is not necessarily bad for consumption, but the big air cell that makes it float proves that it is in your fridge since quite some time already.
The air cell forms itself as a result of the thermic shock the egg experiences when it gets out of the hen. (It is way colder outside …)
And as time passes, the air cell (that happens to be located on the bigger “side” of the egg as a matter of fact) continues to grow : air and gas come in through the porous shell to replace the fluids that evaporate.
You’ve surely already noticed that a hard-boiled egg, once its shell is off, has a little indentation at its base. It is in fact the place where the air cell was, its negative imprint.
Did you know ?
The flashlight and the use-by date
Besides the flotation test, another way to know if the egg is still fresh without breaking it consists in putting it in front of a bright light like the one of a flashlight. With a little experience, you will know if the air cell is of a reasonable size or not.
Otherwise, you can always respect the use-by date which, in Europe at least, is 28 days after the laying date (it’s indicated on the egg or on the packaging) …
To be noted :
If the egg sinks but puts its behind (that famous bigger “side”) upwards, then it’s also better to avoid eating it !