Milk and dairy processing is the conversion, or processing, of raw milk (fresh from the cow) into a number of different products. This processing is done at a dairy plant, where skilled workers and special equipment make sure that milk and other dairy products are safe, nutritious, and delicious. Micro-filtration is the latest way to purify milk. This process uses a membrane strainer to filter most of the harmful bacteria out of milk and is used in addition to pasteurization.