Note 11 — Chapter IX · PHYSIOLOGICAL ACTIVITIES.

The term “fermentation” was originally used to denote the process which goes on in fruit juices or grain extracts when alcohol and gas are formed. Later it was extended to apply to the decomposition of almost any organic substance. In recent years the attempt has been made to give a chemical definition to the word by restricting its use to those changes in which by virtue of a “wandering” or rearrangement of the carbon atoms “new substances are formed which are not constitutents of the original molecule.” It may be doubted whether this restriction is justified or necessary. A definition is at present scarcely possible except when the qualifying adjective is included as “alcoholic fermentation,” “ammoniacal fermentation,” “lactic acid fermentation,” etc. ↩