METHOD OF CITRIC ACID PRODUCING Russian patent published in 1999 - IPC

FIELD: microbiological industry. SUBSTANCE: invention relates to technology of food organic acids production, namely citric acid, by the submerged fermentation method. Method involves hydrolysis of starch suspension by dilution of the starch suspension containing 26-36 wt.-% of dry matter with an enzyme preparation of bacterial α-amylase (0.5-1.5 U amylolytic activity/1 g of starch dry matter), addition of mineral salts followed by fermentation with Aspergillus niger culture. Before salts addition the starch suspension is kept under an excess pressure 0.1 MPa for 30 min. The purified starch suspension, a semiproduct of starch production (concentration of dry matter is 36%) is used as the initial starch-containing raw. EFFECT: broadened raw base, improved ecology of technology. 1 tbl, 4 ex