What happens to an omelet when prepared too far in advance?

When an omelet is prepared too far in advance, it loses its fluffiness due to the structural changes that occur in the eggs. Freshly cooked omelets are light and airy, which is achieved by incorporating air into the egg mixture as it cooks. However, over time, if an omelet is held or stored, the steam and moisture that contributed to its light texture begin to escape, causing the proteins to firm up more than intended. This results in a denser and flatter omelet that lacks the ideal airy texture, leading to a less enjoyable eating experience. Thus, the loss of fluffiness is a direct outcome of over-preparation or prolonged holding of the omelet.