Dumas, a native of the Alais district, where the disease was rampant, urged Pasteur to undertake its investigation.
Shortly afterwards the Pasteur family removed to Arbois, where Louis attended the Ecole primaire, and later the college of that place.
The veteran Biot whose acquaintance Pasteur had made, was incredulous.
In 1857 Pasteur decisively proved that fermentation was a physiological process, for he showed that the yeast which produced fermentation was no dead mass, as assumed by Liebig, but consisted of living organisms capable of growth and multiplication.
Liebig and Pasteur were in agreement on the point that fermentation is intimately connected with the presence of yeast in the fermenting liquid, but their explanations concerning the mechanism of fermentation were quite opposed.