[The role of water in the production and processing of milk (author's transl)].

Water is used in various ways in milk production and dairy industry, thereby becoming part of the food intentionally, inevitably or accidentally. The contamination of the food by water-borne microorganisms occurs directly, much more often, however, indirectly after multiplication of these microorganisms on the cleaned surfaces of the equipment used. Decisive for the influence of these microorganisms on the quality of milk and dairy products are the number and characteristics of the microorganisms, the extrinsic factors and the properties of the food. The various possibilities of an influence resulting from the microbiological quality of the water are exemplarily shown for raw milk, pasteurized milk, butter and cheese. The requirements concerning the water used in milk producing and processing plants are settled in the drinking-water-regulation. The bacteriological requirements of this regulation, however, don't absolutely guarantee a water of good technologic-hygienic quality. Doubts about the use of cooling water, which must not show the quality of drinking water, arise only with regard to pathogenic microorganisms.