In 1857, French microbiologist Louis Pasteur proved in the paper "Mémoire sur la fermentation alcoolique '' that alcoholic fermentation was conducted by living yeasts and not by a chemical catalyst. Pasteur showed that by bubbling oxygen into the yeast broth, cell growth could be increased, but fermentation was inhibited -- an observation later called the "Pasteur effect ''.
who discover the role of yeast in fermentation
Louis Pasteur