Citric Acid Fermentation Process Optimization Research

Citric acid production of the fungus aspergillus Niger Co827 acid level, conversion rate and fermentation period in production is stable. But from the point of production cost, the citric acid fermentation process is more rapid, in the production process control of in-depth study, it is difficult to further improve the citric acid fermentation level, lead to the high production cost.This paper mainly using biostar software and exhaust gas analysis instrument to DO online, in the process of fermentation temperature, pH, produce acid and parameters such as OUR, CER, RQ, correlation analysis, to grope for the fermentation parameters. Docking at the same time a variety of ages,ventilation with carbon dioxide was studied in fermentation process, to optimize the existing citric acid fermentation process.(1)Using 15L,50L fermentation tank combined with aspergillus Niger in the exhaust gas analysis system for fermentation process to study the critical oxygen analysis, the purpose is to strengthen the dissolved oxygen control in the fermentation process, prepare the way for citric acid fermentation optimization control, save energy and reduce consumption.(2) Using biostar software of temperature changes in the process of fermentation and acid yield curve, such as OUR, CER for related analysis, combined with the bacteria morphology change, we grope for the optimal temperature control of aspergillus Niger citric acid fermentation,(3) According to the seed development period of aspergillus Niger RQ, we use shake flask to investigate the best time of the seed planted.(4) The results was determined by the test that ventilation with carbon dioxide in the fermentation process, increasing the concentration of dissolved carbon dioxide in the fermentation system, can improve the level of fermentation, but also have certain restrictions on bacteria growth, will extend certain fermentation period.Through this research,we maste dissolved oxygen changes and the critical oxygen, and the application of CO2 in the fermentation process,so we can provide the direction and basis for fermentation process optimization and better services to improve the fermentation production.