bubbles at the top of the foam will grow larger as the water leaves and the cell walls or film become too weak and break, forming larger bubbles. Whipping aids Whipping aids improve the foaming properties of albumen, a protein found in egg whites, which means a firmer foam will be established in a shorter amount of time. Cream of tartar is an acidic salt which adjusts the pH of egg whites so the proteins will be more soluble, as well as reducing protein denaturation during whipping. If cream of tartar is not used the cake may not reach its maximum achievable volume. Cream of tartar also decolorizes the flavone pigments in flour, giving a final cake that is a bright white color. The whiteness of the cake is also caused by the way cream of tartar creates very small and uniform air bubbles, which gives the cake the appearance of being whiter after baking. Flour The baking process causes the batter to expand and go from a liquid to a solid foam. The proteins will not start to denature until the temperature reaches around . During this rise in temperature the air bubbles will either expand, coalesce, or break. An egg white foam will continue to expand uniformly until the internal temperature reaches – . Based on the ideal gas law, as the temperature increases, the volume of the air bubbles will expand. The temperature will continue to rise, causing the cake to expand at different rates and egg white proteins will gradually denature. Some of the egg white proteins will start to denature and coagulate at around . This establishes the setting of the foam structure. By the time the temperature reaches , all of the egg white proteins will have set in place. The foam structure will decrease slightly or collapse in order to form a solid foam of less volume. This occurs while the cake is still baking, not when it is cooling. The combination of protein denaturation and starch gelatinization determines whether the cake will set or collapse. When proteins denature, they are not in a stable state. In order to stabilize, the denatured proteins will aggregate around air bubbles and within the continuous phase of the batter. The aggregation and overlapping of the proteins forms a very stable network. The flour plays an important role in the texture, structure, and elasticity of an angel