In a dairy, the creamery is the location of cream processing. Cream is separated from whole milk; pasteurization is done to the skimmed milk and cream separately. Whole milk for sale has had some cream returned to the skimmed milk. The creamery is the source of butter from a dairy. While cream is an emulsion of fat-in-water, the process of churning causes a phase inversion to butter which is an emulsion of water-in-fat. Excess liquid as buttermilk is drained off in the process.