The dairy product made by churning cream until the fat separates is butter. Churning agitates cream until the membranes surrounding its microscopic fat globules break, allowing the fat to clump together.
Cream begins as a water-based emulsion containing dispersed milk fat. During churning, the fat globules collide and merge into grains that eventually form a continuous mass. The liquid left behind is buttermilk, which is drained away; the butter is then worked to distribute moisture and create a smooth texture.
People have made butter for centuries using simple containers and hand-powered churns. Traditional churns used a plunger or paddles, while modern commercial production relies on controlled cream separation, cooling, agitation, and washing. Salt may be added, but unsalted butter is also common, especially in baking.
Butter is sometimes confused with cream cheese because both are spreadable dairy products, but they are made differently. Cream cheese is produced by coagulating milk and cream, while butter is primarily the concentrated fat phase created when cream is churned. The result is a water-in-fat emulsion rather than cream’s fat-in-water emulsion.