1. Open it directly: The simplest way is to open the egg directly if you want to know whether the egg is bad or not. If the egg white is mixed with the yolk, it means that the egg has gone bad. If you smell it carefully, you will smell a rancid smell. The yolk of the egg that is not bad is like a ball, and the egg white is gathered around the yolk, so the egg cannot be eaten. Although this method is the most direct, it is not suitable for tea eggs and boiled eggs.
2. Float test: pour water into a cup, and then put the egg in it. If the egg lies flat on the bottom of the water, it means that the egg is very fresh and has not gone bad. If the egg is tilted or upright in the water, it means that the egg has been stored for a long time. If the egg floats on the water, it will go bad, so don't eat it.