Bacterial Control in Milk Plants

Abstract

Milk inspectors and health officials should not rest assured of a safe product because of the mere presence of a milk pasteurizing, plant in their city. Special attention must be given to the operation of such a plant in view of the fact that unless it is properly operated it may become a chance source of infection to the community. In many instances, only an attempt at the process of pasteurization is being made. This is due to either a lack of pr(~per attention and responsibility or to the absence of understanding, or the part of the operators, as to the functions and reasons for the process. Bacteriological control of the process of pasteurization and of the condition of the subsequent containers and contact surfaces is essential. This examination should not be left entirely to the pasteurizing plant, but should be made frequently by competent officials under the direction of milk inspectors or health officials Who are responsible for the condition of the milk supply and of the health of the community. In considering the efficiency of various pasteurizing processes, it should be understood that the percentage reduction of bacteria in raw milk by heating does not form a measure of safeness of the final product. After heating, the so-called pasteurized milk is changed from its original condition and any inoculation subsequent to the heating introduces an uncertain element which may be of concern and which may void the reduction in bacteria already secured by heating the milk. In the examination of milk to determine the percentage of reduction due to the heating process, a series of samples should be taken aseptically at intervals at the points representing definite stages in the pasteurizing process. It is only in this manner