7-8 minutes. The time for steaming eggs should not be too long, otherwise, not only the color of the steamed eggs will change, but also the taste will get old, the shape will be honeycomb-shaped, not good-looking, and it will not taste good. It is best to mix the steamed egg liquid with warm water and steam it for about 7 minutes to avoid water vapor dripping into it after turning off the fire. If there is more steamed egg liquid, it can be appropriately extended for 2-3 minutes.

When raw eggs are boiled in boiling water for more than 10 minutes, a series of chemical reactions will occur inside raw eggs. Protein's function will be more and more inseparable, and it is not easy to get in touch with protein-pepsin in gastric acid, so it cannot be digested and absorbed. Protein contains methionine. After long-term heating, sulfate dissolves and reacts with iron in egg yolk to produce iron sulfide and ferrous sulfide. This is also the reason why the surface layer of egg yolk will cause dark green.