How do various fermentation pathways differ?

Fermentation pathways are distinguished primarily by the enzymes and products involved in each type. Different pathways utilize specific enzymes to catalyze reactions that convert substrates into various end products. For example, alcoholic fermentation primarily produces ethanol and carbon dioxide through the action of alcohol dehydrogenase, while lactic acid fermentation generates lactic acid facilitated by lactate dehydrogenase.

Although fermentation can vary in energy yields, the fundamental distinction lies in the specific biochemical reactions and the resulting metabolites. Each type of fermentation is adapted to the metabolic needs of different organisms or conditions, reflecting the role of the enzymes and the biochemical pathways utilized.

While the type of organism does influence the fermentation pathway—such as yeast predominantly conducting alcoholic fermentation, and muscle cells switching to lactic acid fermentation under anaerobic conditions—the variation in pathways is rooted in the enzymes and products generated. Oxygen requirements are not typically associated with fermentation since these processes occur in anaerobic conditions, further emphasizing the importance of the enzymes and products in defining different fermentation pathways.