Duck Royal Icing Sugar Decorations. Use on cakes, cake pops, deserts and cupcakes Measure 7/8inches each Perfect for baby showers, and more. Fully edible. Ingredients: Confectioner’s sugar, cornstarch, egg whites, vegetable gum, sodium, aluminum sulfate, citric acid, cream of tartar, FD&C food colors. Duck Royal Icing Sugar Decorations. Use on cakes and cupcakes. Perfect for baby showers, and more. Fully edible. Ingredients: Confectioner’s sugar, cornstarch, egg whites, vegetable gum, sodium, aluminum sulfate, citric acid, cream of tartar, FD&C food colors.