Detection of cow milk in goat milk by polyacrylamide gel electrophoresis

Pasteurized goat milk was adulterated with increasing proportions of cow milk and submitted to polyacrylamide gel electrophoresis. A frontal band, missing from the pattern of genuine goat milk and possessing the same electrophoretic mobility as bovine alpha S1-casein, was expressed. The area of this zone was directly proportional to the amount of cow milk added to the goat milk.