Cream or jam can't stick in the cookie house. These two materials take too long to dehydrate and harden. This effect is definitely not as good as icing. In icing, sugar is twice as much as egg white. Sugar is a kind of food substance with high osmotic pressure, which can be forcibly exchanged from the water in microbial cells, causing microorganisms to dehydrate and die, so the high-sugar formula has the function of inhibiting microbial growth and prolonging the shelf life of food.

Therefore, frosting can be regarded as sugar-cured egg white, which can be eaten after being packaged and dustproof.