Louis Pasteur

Louis Pasteur is the 19th-century biologist and chemist whose work with germs and micro-organisms opened up new fields of scientific inquiry, aided industries (ranging from wine to silk), and made him one of the world's most celebrated scientists. Pasteur became a professor of chemistry at the University of Lille in 1854, and soon began studying fermentation in wine and beer. He became convinced "the germs of microscopic organisms abound in the surface of all objects, in the air and in water." He determined that such micro-organisms could be killed by heating liquid to 55 degrees Celsius (about 130 degrees Fahrenheit) or higher for short periods of time. This simple process became known as pasteurization, a process used today in milk and many other beverages. Pasteur then turned his attention to other aspects of microorganisms. He virtually created the science of immunology, showing that certain diseases (like rabies) could be prevented by vaccination (his term), that is, injecting animals with weakened forms of the disease. So great were Pasteur's successes that an international fund was raised to create the Louis Pasteur Institute in 1888. Pasteur worked with the institute until his death, and it continues today as a center of microbiology and immunology.