On-line Control System of Fed-batch Culture with Culture Phase Recognition using Fuzzy Inference

Abstract An on-line control system with culture phase recognition based on a fuzzy sets theory was developed to realize versatile control of a bioreactor with culture phase transition during cultivation for enzyme production. The system makes it possible to recognize the current culture phase in a bioreactor and to provide a suitable control policy corresponding to the current process state during fed-batch culture.The system was tested by using a fed-batch culture for α-amylase production.The experimental results showed that it was able to recognize a change of the microbial state as a culture phase transition and to control the feeding rate of the substrate.