Abstract: A method and apparatus for ascertaining and measuring the quality of milk by analyzing reflected or absorbed colors or both with which the milk is irradiated. The milk is thus irradiated with three colors of light in wavelengths of red, green and blue and the intensity and color of the light reflected by the milk or absorbed thereby, or both, is measured. The light sources are periodically switched off whereby the receiving sensors measure the same red, green and blue wavelengths due to background sources to the extent that they are reflected or absorbed or both by the milk. This data is then compared with data with the light sources switched on to produce the net data which is relevant to the milk as it is being received from the animal being milked.