Angel Food Cake

The primary difference is that angel food cake is a true foam cake made entirely without butter, cooking oil, or egg yolks. It relies solely on the microscopic air pockets whipped into egg whites to give it volume and structural lift. Traditional sponge cakes typically include whole eggs and sometimes melted butter, making them significantly richer and denser.

Angel food cake batter is extremely light and delicate, and it needs a hot, textured surface to physically cling to as it rapidly rises in the oven. For this reason, it is traditionally baked in a specialized tube pan featuring a hollow, central cone. The center tube provides the necessary grip for the fragile egg-white foam to climb up and bake evenly without collapsing in the middle.

Cream of tartar is a highly acidic powder that is crucial for chemically stabilizing the whipped egg whites in angel food cake. It helps the egg whites hold their stiff peaks much longer, increases their overall volume, and prevents them from deflating during the folding process. It also helps maintain the pale, bright white interior color of the baked cake.

To prevent a freshly baked angel food cake from deflaling and turning dense as it cools, it must be cooled completely upside down. Typically, bakers invert the tube pan by balancing it on the metal legs attached to the pan or over the neck of a sturdy glass bottle. Leaving it suspended upside down for about two hours ensures the internal structure sets and locks into place before it is removed.