Judy - from Florence, SC
All cakes will shrink slightly from the sides of their pan when taken out of the oven. If your cakes are shrinking more than normal they probably contain a high percentage of egg whites. Egg white based cakes (for example angel food cake) use egg white protein and air to provide structure for the cake. If the cakes are cooled upward, the weight of the cake will depress the air pockets resulting in cake shrinkage. For this reason, angelfood cakes are cooled upside down. To decrease the shrinkage of your cakes, you may want to add more whole eggs to your recipe or bake your recipe in an angel food cake pan, cooling the cake upside down.