"In this process, biomass feedstock is first fed to the bacteria Clostridium tyrobutyricum, where a large percentage is converted into butyric acid and hydrogen. In the second process, the butyric acid is fed to the bacteria Clostridium acetobutylicum, where it is converted into butanol. Ramey has claimed a 42% butanol yield from this process."
Cows make Butyric Acid in their rumens, but it's hard to pipe it out.
"The rumen stinks. This is because microbes in the rumen produce stinky organic acids. The billions of microbes in the rumen quickly use up all the oxygen. Because there is no oxygen, the rumen is anaerobic. When oxygen is lacking, microbes must get their energy from anaerobic respiration or from fermentation. In anaerobic respiration, microbes breathe compounds other than oxygen for energy. Fermentation is the breaking down of organic molecules into smaller molecules such as organic acids like butyric acid and valeric acid that stink."
"Butyric acid, IUPAC name n-Butanoic acid, or normal butyric acid, is a carboxylic acid with structural formula CH3CH2CH2-COOH. It is notably found in rancid butter, parmesan cheese, and vomit, and has an unpleasant odor and acrid taste, with a sweetish aftertaste (similar to ether)."
