Patent attributes
An object to be solved by the present invention is to provide a method for producing organic acid with higher fermentation efficiency. The present invention provides a method for producing organic acid from an organic material by allowing bacterial cell or treated products thereof to act on an aqueous reaction solution containing the above organic material, which is characterized in that after completion of the reaction, the aqueous reaction solution is recovered, cell or treated products thereof are separated from the recovered aqueous reaction solution, and the separated cell or treated products thereof are allowed to act on a fresh aqueous reaction solution, so that the cell or treated products thereof are repeatedly used.