pasteurization

pasteurization , partial sterilization of liquids such as milk, orange juice, wine, and beer, as well as cheese, to destroy disease-causing and other undesirable organisms. The process is named for the French scientist Louis Pasteur , who discovered in the 1860s that undesired fermentation could be prevented in wine and beer by heating it to 135°F (57°C) for a few minutes. Milk is pasteurized by heating it to about 145°F (63°C) for 30 min or by the "flash" method of heating to 160°F (71°C) for 15 sec, followed by rapid cooling to below 50°F (10°C), at which temperature it is stored. The harmless lactic acid bacteria survive the process, but if the milk is not kept cold, they multiply rapidly and cause it to turn sour.

pasteurization Controlled heat treatment of food to kill bacteria and other microorganisms, discovered by French chemist Louis Pasteur in 1862. Milk is pasteurized by heating it to 72°C (161.6°F), and holding it at that temperature for 16 seconds. Ultrapasteurization is now used to produce UHT (ultra-heat-treated) milk; it is heated to 132°C (270°F) for one second to provide a shelf-life of several months.