Louis Pasteur a French chemist, supported the idea that fermentation was a biological process.
Justus von Liebig, a German chemist, supported the idea that fermentation was a mechanical process.
He believed that vibrations emanating from the decomposition of organic matter would spread to the sugar resulting in the production of solely carbon dioxide and alcohol.
Given that the ferment's susceptibility to change, it is submitted to decomposition, by the action of air (from which oxygen is provided), water (from which moisture is obtained), and a favorable temperature.
Pasteur thought that in pure sugar-water, yeast was both growing and disintegrating, and developed experiments to support his theories.
Pasteur was furious, and suggested the Royal Academy hire a third scientist who would replicate his experiments and verify his results in order to support his theories.
[7] The famous controversy between Pasteur and Liebig over the nature of alcoholic fermentation was uncovered by Eduard Büchner, a German chemist and zymologist.
Influenced by his brother Hans, who became the famous bacteriologist, Büchner developed an interest in the fermentation process in which yeast breaks down sugar into alcohol and carbon dioxide.
He published his first paper in 1885 which revealed that fermentation could occur in the presence of oxygen, a conclusion contrary to the view held by Louis Pasteur.
However, when he attempted to preserve the fluid in concentrated sugar, he was startled to observe carbon dioxide being released, a sign that fermentation was taking place.
He believed this was what Berzelius defined as catalysts, or the force for chemical reactions of mineral, organic and living matter.
On the other hand, the conflicting ideas sped up the research in the area of fermentation and enzymes through other scientists and chemists.