Angel Food Method

This type of cake contains neither fat nor chemical leaveners. It relies solely on stabilized egg-white foam for leavening. The foaming power of the egg whites results from a combined effort of various proteins to increase the thickness (viscosity) of the albumen and produce a fine mesh of foam (tiny bubbles) that will hold together for a time if properly combined with the sugar. Angel food batters have a much higher sugar content than any other sponge or butter cake. Although sugar has a mixed influence in the whipping stage, where it acts to delay the foaming of the whites, it stabilizes the foam once it is whipped, especially in the oven, where sugar is necessary to prevent a total collapse. Sugar does this by forming hydrogen bonds and delaying evaporation. Mixing and baking an angel food cake successfully is a delicate procedure.