Eggs are divided into three layers: yolk, egg white and eggshell. If the fire is too strong when cooking eggs, the egg white with low freezing temperature outside the egg yolk will quickly solidify and harden, thus preventing the heat from continuing to be transferred to the egg yolk and affecting the solidification of the egg yolk with high freezing temperature, so that the boiled egg white is cooked, but the egg yolk is not cooked. If the eggs are boiled for too long, protein will be excessively denatured, and the eggs will become hard and unpalatable, which will affect digestion and absorption. So pay attention to the method of boiling eggs. Eggs should be put into the pot with cold water and then heated slowly. After the water boils, turn off the fire for about two minutes, keep the temperature for five or six minutes, and then take it out. You can eat them.