A low maintenance conductivity sensor for detecting mastitis

Abstract The relationship between the conductivity of milk and the presence of sub-clinical mastitis is well established but the “on line” measurement of conductivity has proved difficult owing to the fouling of electrodes by the fats and solids in the milk. This paper describes the development of a mastitis sensor which has no electrodes in contact with the milk. The electromagnetic theory defining its operation is discussed and a set of equations is derived from the theory. These equations are used to optimize the signal to noise ratio whilst minimizing problems due to component drift and variability between sensors. The device has been used successfully to measure the conductivity of electrolytic solutions.