A Study of Some Factors in the Butter Churning Process

Summary 1. A study of the distribution of casein between water and a mineral oil-water interface tends to confirm the conclusion of Wiegner with respect to the thickness of the interfacial film. 2. Results are described, obtained in churning certain modified creams. The relative electrical potential on the butter-fat globules, and the viscosity of the interglobular solutions were determined. These two factors appear to have very little, if any, effect on churning time. 3. It is suggested that churning is due to the setting free of butter fat from the less stable globules, followed by a cementing of the more stable protected globules into clumps, by the free butter fat. 4. In support of this view, we have been able to produce butter, without churning under conditions that favor a decrease in stability of the fat globules.