The review is focused on several aspects of butyric acid production: butyri
c acid-producing bacterial strains, the characteristics of the genus Clostr
idium (the bacterium most used for butyrate production), and alternative me
thods of obtaining butyric acid by alcohol biotransformation. Further, the
main metabolic pathways of butyrate production, and possibilities for their
control are outlined. Batch, fed-batch or continuous fermentation combined
with cell recycle or Immobilization are applicable for anaerobic fermentat
ions using Clostridium as the production strain, The best process comprises
a combination of high cell concentration and slowly growing biomass, in ad
dition to high production selectivity and low inhibitory effects of the end
-product, Inhibitory effects may be avoided by on-line removal of the end-p
roduct, Extraction alone or extraction combined with simultaneous stripping
of the organic phase (liquid membrane) into the second aqueous phase (pert
raction) seem to be the most suitable methods for online butyrate removal,
The biocompatibility and the distribution coefficient of the organic phase
under fermentation conditions should be considered before designing a ferme
ntation apparatus.