<Li> The high concentration of lactic acid (the final product of fermentation) drives the equilibrium backwards (Le Chatelier's principle), decreasing the rate at which fermentation can occur, and slowing down growth . </Li> <Li> Ethanol, into which lactic acid can be easily converted, is volatile and will readily escape, allowing the reaction to proceed easily . CO is also produced, but it is only weakly acidic, and even more volatile than ethanol . </Li> <Li> Acetic acid (another conversion product) is acidic, and not as volatile as ethanol; however, in the presence of limited oxygen, its creation from lactic acid releases additional energy . It is a lighter molecule than lactic acid, that forms fewer hydrogen bonds with its surroundings (due to having fewer groups that can form such bonds), thus is more volatile and will also allow the reaction to move forward more quickly . </Li> <Li> If propionic acid, butyric acid, and longer monocarboxylic acids are produced (see mixed acid fermentation), the amount of acidity produced per glucose consumed will decrease, as with ethanol, allowing faster growth . </Li>

Fermentation is a naturally occurring process that produces