Cream of tartar in angel food cake contributes to which aspect of the cake?

Cream of tartar plays a crucial role in the structure and stability of angel food cake. It is an acid, specifically a type of acid salt, that helps to strengthen the proteins in egg whites. When beaten, egg whites create a foam that gives angel food cake its light and airy texture. The presence of cream of tartar stabilizes this foam, allowing the egg whites to hold onto the air they incorporate during whipping.

Stabilizing the foam is essential for achieving a larger volume in the cake. As the cake bakes, the foamed egg whites expand, leading to a light and fluffy texture. The combination of a stable foamy structure and the action of the leavening during baking results in a cake that is significantly larger in volume.

In summary, cream of tartar contributes to the larger volume of angel food cake by stabilizing the whipped egg whites, which is vital for its characteristic height and texture.