What does folding in the egg whites do to a cake?
Folding egg whites into the cake batter is a technique that is used in this recipe. The egg whites are first whipped to a peak state. Then they are folded into the cake batter. Whipping the egg whites is done to introduce air into them. By folding the whipped egg whites into the batter we are thus introducing additional air into the cake batter which in turn help the texture of our cake become become less dense when baked.