Butter cream or buttercream or mock cream is a type of icing used inside cakes, as a coating, and as decoration. In its simplest form, it is made by creaming butter with powdered sugar, although other fats can be used, such as margarine. Colorings and flavorings are often added, such as cocoa powder or vanilla extract.
Simple buttercream, also known as American buttercream, is made by creaming together fat and powdered sugar (also known as "icing" or "confectioner's" sugar) to the desired consistency and lightness. Small quantities of whole eggs, egg whites, egg yolks, or milk may be included. Some recipes also call for non-fat milk solids. Due to a high sugar content, the frosting can form a thin crust, which prevents sticking.
Sometimes called Rose Paste, this buttercream is creamed much less than a regular simple buttercream resulting in a stiff paste suitable for making flowers and other cake decorations. It is usually the sweetest of all the buttercreams.
Also known as Swiss buttercream or Italian buttercream, this buttercream is similar in preparation to a French buttercream. A boiling syrup of sugar and water cooked to soft-ball stage is poured over beaten egg whites to create a meringue. The sugar syrup essentially cooks the egg whites, eliminating most health concerns. Fat is added to the meringue as it cools. Frequently, when adding in the butter or shortening, the mixture will separate and look "curdled". Extensive mixing is needed to incorporate the ingredients. This is the most commonly used frosting for bakery cakes, and it does not form a crust.
French buttercreams are made by beating a sugar syrup which has reached the soft-ball stage into beaten egg yolks and whipping to a light foam. Softened butter is then whipped in. This icing is very rich, smooth, and light. French buttercreams tend to melt faster than other buttercreams due to the high content of fat from the egg yolks and butter.
Pastry cream types, sometimes referred to as German buttercreams, are made by beating together thick pastry cream and softened butter, and may be additionally sweetened with extra confectioners' sugar. Similarly, a light custard can be made and beaten with butter.
Fondant buttercream is made by creaming together equal parts fondant and butter.
The choice of fat in a buttercream frosting relates closely to the stability. Often, some amount of vegetable shortening is combined with butter for better consistency and resistance to heat.
Sweet cream unsalted butter is traditionally the fat of choice for buttercreams, as evidenced by the name. Butter provides a more delicate texture and superior flavor and mouthfeel (texture) when compared to vegetable shortening. Butter melts at a lower temperature, though, making it more difficult to use. The coloring provided by the butter is slightly off-white in the final frosting.
Hydrogenated vegetable shortenings (margarine) have become a popular ingredient in commercial icings during the 20th century because they are cheaper and more stable at room temperature than butter. Icings made with vegetable shortening are more stable in warm temperatures and therefore easier to work with than butter. The whiter color is also favored, especially for wedding cakes. However, shortening does not dissolve in the mouth like butter, leading to a heavy, greasy feel inside of the mouth. The flavor of the buttercream is also not as intense, and the resulting product raises health concerns due to the presence of trans fats.
Flavorings are commonly present in a buttercream frosting. Vanilla and chocolate are the most common additions. Clear vanilla extract can be used to create a lighter-colored frosting. For chocolate buttercreams, cocoa powder or melted chocolate is added during the creaming stage. Liqueurs or extracts, such as almond or peppermint, can also added. For meringue-type and French buttercreams, the sugar syrup can be prepared with other liquids such as juice for increased flavor. Food coloring can be added easily to any buttercream.
Most buttercreams can be left at room temperature without melting. Buttercreams made with shortening and a higher sugar content withstand warmer temperatures better than those made solely with butter. Cooling buttercream will cause it to harden. If a frosted cake is cooled, the buttercream may crack.
When using buttercream to frost a cake, it is best to work with it when it is soft and spreadable. Icings may be stored, covered, in the refrigerator for several days. Before use, the icing needs to sit outside the fridge so it can come up to room temperature. If it must be warmed quickly or if it curdles, it can be heated over warm water (such as a bain marie or double boiler) and beaten until it becomes smooth again. Avoid directly heating the buttercream.