process for the production of normal buttersaeure by vergaerung a zuckersubstrats in presence of at least one strain of the species of clostridium.

摘要

A process is described for producing, in a reaction zone, a mixture of organic acids or of the corresponding salts containing a major proportion of n-butyric acid or of its corresponding salt, by fermenting an initial reaction mixture containing a sugar substrate in the presence of at least one strain belonging to the Clostridium species. According to the invention the following stages are carried out: a) the strain is fed with the substrate at an initial concentration of between 1 and 80 g of substrate per litre of initial reaction medium, b) the substrate concentration is allowed to decrease by at least 20% of its initial value and to a value such that it is between 0 and 30 g of substrate per litre of initial reaction medium, c) the strain is fed with the said substrate at a rate of between 0.01 and 25 g per litre of initial reaction medium and per hour and such that the residual concentration of the said substrate during the feeding period is not more than 80 g/l of initial reaction medium, and d) the mixture of acids or of salts thus produced is recovered. o