What is a common indication that an egg is well-cooked when frying?

A common indication that an egg is well-cooked when frying is firm whites. When egg whites are properly cooked, they transition from a clear, viscous state to a firm, opaque texture. This transformation signifies that the proteins in the egg whites have coagulated, which is essential for both food safety and achieving the desired culinary results.

Firm whites ensure that the egg is cooked thoroughly, which helps reduce the risk of foodborne illnesses associated with undercooked eggs. Additionally, cooking until the whites are firm contributes to the overall texture and mouthfeel of the dish, providing a satisfying experience when eaten.

While brown edges can suggest cooking, they often indicate a risk of overcooking or burning. A fluffy texture is more relevant for scrambled eggs rather than fried eggs, and a glossy surface is typically a sign of undercooking or insufficient heat, as fully cooked whites tend to lose that gloss. Thus, firm whites remain the best marker for a well-cooked fried egg.