[1] : The Collaborative International Dictionary of English v.0.48

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 proteins, 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
see also:
barm fervent a b enzymes soluble ferments 
chemical ferments acetic ferment butyric ferment fermentation globular protein 
enzyme ferment oils 

Enzymes >> E Words
Enzymes, definition of term: Enzymes
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