Butter, a dairy product, is produced by churning fresh or fermented cream or milk to separate the butterfat from the buttermilk. This method of converting milk fat into butter has been employed since ancient times as a means of preserving milk fat. While butter is primarily made from cow's milk, it can also be derived from the milk of other mammals such as sheep, goats, buffalo, and yaks.
The earliest butter churns consisted of a wooden container and a plunger, which were used to agitate the cream until butter formed. These were commonly referred to as plunge churns or dash churns. Subsequently, butter churns were made with containers crafted from wood, ceramics, or galvanized iron, incorporating paddles for the churning process. Later, centrifugal butter churns were introduced, where the paddles remained fixed while the container spun, enabling better separation of butter from buttermilk.
Factory butter making was virtually nonexistent until the mid-nineteenth century. Most butter was produced on farms using cream obtained through gravity creaming. The cream was poured into a wooden churn and subjected to shear and mild aeration with the assistance of a stirrer or by rotating the vessel. Once fat clumps formed, the buttermilk was separated, and the resulting mass of butterfat was collected and excess moisture was removed.
Towards the end of the 19th century, the commercial cream separator was introduced, and by the mid-20th century, continuous churns became commercially available.
The first butter factories emerged in the United States in the early 1860s. In the late 1870s, the centrifugal cream separator was introduced, eliminating the need to rely on the natural rising of cream to the top of milk. Initially, whole milk was transported to butter factories where cream separation took place. However, as cream-separation technology became more compact and affordable, farmers began separating cream on their own farms and sending only the cream to the factories.
The recognition of the benefits of heat treatment in improving the shelf life of dairy products led to the establishment of creameries where milk was separated. The increased availability of larger quantities of cream further spurred the mechanization of butter making.
Evolution of churning process in butter production
