Clarified butter is butter with the milk solids and water removed. To clarify butter, it is heated to break the emulsion, which causes its different components to separate according to density and chemical makeup. The milk solids turn into a foam at the top, which can be cooped away with a spoon. At the bottom lies a thin layer that includes proteins, phospholipids, and the aqueous layer, which is predominantly water along with some dissolved milk sugar (lactose) and minerals. This milky casein layer can be discarded after the butterfat solidifies a it cools. Clarified butter has a higher smoke point than while butter and will keep longer in the refrigerator (for three to four weeks) or the freezer (for four to six months) without picking up other flavors and odors.
