chemical ferments

Ferment Fer"ment, n. [L. fermentum ferment (in senses 1 & 2), perh. for fervimentum, fr. fervere to be boiling hot, boil, ferment: cf. F. ferment. Cf. 1st {Barm}, {Fervent}.] 1. That which causes fermentation, as yeast, barm, or fermenting beer. [1913 Webster]

Note: Ferments are of two kinds: ({a}) Formed or organized ferments. ({b}) Unorganized or structureless ferments. The latter are now called {enzymes} and were formerly called {soluble ferments} or {chemical ferments}. Ferments of the first class are as a rule simple microscopic vegetable organisms, and the fermentations which they engender are due to their growth and development; as, the {acetic ferment}, the {butyric ferment}, etc. See {Fermentation}. Ferments of the second class, on the other hand, are chemical substances; as a rule they are proteins soluble in glycerin and precipitated by alcohol. In action they are catalytic and, mainly, hydrolytic. Good examples are pepsin of the dastric juice, ptyalin of the salvia, and disease of malt. Before 1960 the term "ferment" to mean "enzyme" fell out of use. Enzymes are now known to be {globular protein}s, capable of catalyzing a wide variety of chemical reactions, not merely hydrolytic. The full set of enzymes causing production of ethyl alcohol from sugar has been identified and individually purified and studied. See {enzyme}. [1913 Webster +PJC]

2. Intestine motion; heat; tumult; agitation. [1913 Webster]

Subdue and cool the ferment of desire. --Rogers. [1913 Webster]

the nation is in a ferment. --Walpole. [1913 Webster]

3. A gentle internal motion of the constituent parts of a fluid; fermentation. [R.] [1913 Webster]

Down to the lowest lees the ferment ran. --Thomson. [1913 Webster]

{ferment oils}, volatile oils produced by the fermentation of plants, and not originally contained in them. These were the quintessences of the alchemists. --Ure. [1913 Webster]