Can you still eat eggs that have grown mold and gone bad?

You cannot eat them. If the shell is moldy, it will inevitably cause the inside to be infected with bacteria, causing the egg to spoil and produce toxic substances, so it must not be eaten.

There are many factors that cause spots on eggs: it may be inflammation of the oviduct of the hen that laid the egg, or it may be a feed problem that causes spotted eggs, or it may be caused by the egg becoming moldy and spoiled.

Because there are many pores on the eggshell, bacteria and mold will enter the inside of the egg through these pores. Black spots appear on the inner wall of the eggshell, but the yolk and egg white have not gone bad. This is also because mold enters the shell through the pores, damages the shell membrane inside the shell, and the mold grows and gathers into black spots.

Some eggs are exposed to rain or moisture, which will damage the protective film on the surface of the eggshell, and will also allow bacteria to invade the inside of the egg and cause mold and spoilage. Although such eggs show no obvious signs of spoilage on the surface, the quality of the egg has actually declined, and it is not recommended to eat them.

How to store eggs

Eggs should be stored upright, with the large end facing up. Fresh eggs have thick egg white, which can effectively hold the yolk in place. However, as storage time lengthens, the mucin in the egg white will gradually thin under the action of protease and lose its ability to hold the yolk in place. Since the yolk has a lower specific gravity than the egg white, if the egg is placed horizontally, the yolk will float upward, get close to the eggshell, and become a stuck-yolk egg or a near-shell yolk egg. If the egg is placed upright with the large end facing up, there will be an air chamber inside the large end, and the gas inside will prevent the yolk from getting close to the eggshell.