METHOD FOR PRODUCING ORGANIC ACID

摘要

A method for producing an organic acid by fermentation from a sugar, wherein the production efficiency of the organic acid is improved. A method for producing an organic acid, in which an organic acid is produced in fermentation equipment by fermenting a sugar using Schizosaccharomyces pombe that has been genetically modified to be capable of fermentatively producing an organic acid, and the organic acid is obtained from the fermented liquid removed from the fermentation equipment, wherein the method is characterized in that the combination of the following fermentation step and the following removal step subsequent to this fermentation step is repeated at least twice. Fermentation step: a step for setting the sugar concentration at the starting point of fermentation at 20 g/L or higher by adding a raw material solution containing sugar into fermentation equipment, and conducting fermentation while controlling the dissolved oxygen concentration of the fermented solution to a range from 5 ppb to 500 ppb. Removal step: a step for removing some of the fermented solution from the fermentation equipment, the step beginning when the sugar concentration of the fermented solution has reached a sugar concentration × (unit: g/L, × ≤ 10) determined in advance, wherein the step ends with the removal of a prescribed amount of fermented solution.