Frosting is a thick and fluffy coating of cream or butter. Icing is a thin and sugary glaze spread that hardens on cooling. They are both used for decorating cakes, muffins and pastries.
According to Food Timeline, the first recipe for icing was documented by Elizabeth Raffald in 1769 in the Experienced English Housekeeper. The first icing were a boiled composition of the finest available sugar, egg whites and sometimes flavoring which was poured on the cake. The cake was then returned to the oven for a while. When removed the icing cooled quickly to form a hard, glossy ice-like covering.
In 1915, Mrs. Fred W. Gurney created the first buttercream recipe, and Fannie Farmer followed with many more recipes in 1918 and 1923.
Frosting is usually made with a cream or butter based. Colors are added to the cream before decorating.
Icing is typically made with a sugar base, although it can also be made with egg whites, butter or cream. Colors are added to the sugary base before it hardens up.
Frosting is thick and gooey, and can look fluffy. It is opaque. It can also hold shapes, like rosettes and shells. It is soft to the touch and creamy.
Icing is thin and glossy. It is usually, but not always, opaque. It is more liquid, but it hardens when it dries out.
Frosting is usually used on cakes, for example the buttercream on the top of a birthday cake or a cupcake.
Icing is used to create a thin glaze on cakes and pastries.
Although both icing and frosting can be used interchangeably, some general and popular uses of icing or frosting are used are:
- Cookies - icing of sugar and water/lemon juice.
- In between layers of a cake - a soft and flully frosting of buttercream/cream cheese frosting.
- On top of cakes or cupcakes - both icing and frosting are used.
There are several specialized equipment like cones, decorating spatulas, smoothers, cutters etc that are available for decorating with icing or frosting. A few of these are available on Amazon.com.