(1822-1895) French chemist and microbiologist who discovered that fermentation is caused by microorganisms and developed the germ theory of disease. He also created a vaccine for rabies, which led to the foundation of the Pasteur Institute in Paris 1888.
Pasteur saved the French silkworm industry by identifying two microbial diseases that were decimating the worms. He discovered the pathogens responsible for anthrax and chicken cholera, and developed vaccines for these diseases. He inspired his pupil Joseph Lister’s work in antiseptic surgery. Pasteurization to make dairy products free from the tuberculosis bacteria is based on his discoveries. See also food technology.
Pasteur was born in Dôle in E France and studied in Paris at the Ecole Normale Supérieure. He was professor at Strasbourg 1849–63, moving to the Ecole Normale Supérieure to institute a teaching program that related chemistry, physics, and geology to the fine arts. Also in 1863 he became dean of the new science faculty at Lille University, where he initiated the novel concept of evening classes for workers. In 1867 a laboratory was established for him with public funds, and from 1888 to his death he headed the Pasteur Institute.
A query from an industrialist about wine- and beermaking prompted Pasteur's research into fermentation. Using a microscope he found that properly aged wine contains small spherical globules of yeast cells whereas sour wine contains elongated yeast cells. He proved that fermentation does not require oxygen, yet it involves living microorganisms, and that to produce the correct type of fermentation (alcohol-producing rather than lactic acid-producing) it is necessary to use the correct type of yeast. Pasteur also realized that after wine has formed, it must be gently heated to about 50şC/122şF —pasteurized—to kill the yeast and thereby prevent souring during the aging process.