Pasteurization is a process every dairy goes through before it makes it to the grocery store. It is done in order to eliminate diseases in the milk and make it safe for consumption. The process includes the milk being heated to a certain temperature and holding it there for a certain amount of time (either lower temperatures for longer or higher temperatures for shorter). Some pasteurizing can actually increase shelf life and decrease refrigeration needs, though most milks last for a limited amount of time and need refrigeration. Some other products, such as eggs, are also pasteurized, but milk is the most common product to be pasteurized. Milk sold in supermarkets in always pasteurized for your safety!