Why are some boiled eggs empty?

When we eat boiled eggs, we sometimes feel strange. It is obvious that the eggs are full before they are boiled. Why is it empty when it is cooked, and sometimes a large piece is empty?

In fact, the empty part of the egg is called the air chamber, which has two main functions. When the eggs hatch, the unhatched chicks need to breathe air, and the chicks breathe air in the air chamber. There are more than 70 holes in the eggshell that we can't see with the naked eye (so don't wash the eggs first when you save them), most of which are distributed near the air chamber. In this way, the outside air can enter the eggshell through these holes and be stored in the air chamber for the chickens to breathe.

The air chamber also played a role. Under the influence of external temperature, the volume of egg liquid will expand with heat and contract with cold. With this air chamber, when the volume increases, the eggshell will not break.

When the eggs are cooked, this air chamber is set aside, but generally speaking, after the eggs are cooked, half of them will not be empty. If there are too many blanks when the eggshell is intact, it is basically certain that the egg has been broken and cannot be eaten.