Abstrait

Batch-to-batch reproducibility of fermentation processes by robust operational design and control

Sebastian Schaepe, Artur Kuprijanov, Rimvydas Simutis, Andreas Lubbert, Michael Pohlscheidt and Marco Jenzsch*

Batch-to-batch reproducibility aims to keep every batch of the fermentation process exactly on track. This can be obtained by two methods: first, which is currently most often applied in industrial fermentation processes, is operating the fermentation processes in the open-loop control mode. This requires robust (i.e., failure-tolerant) fermentation strategies as corrections upon unexpected deviations from the desired path are not intended. The second control method counteracts for distortions in the process state variables by corrective measures using advanced closed-loop or feedback control modes. This is less frequently used as most companies have difficulty in making precise state estimations, which are a prerequisite for feedback control. In this review we discuss various aspects of both techniques that are considered decisive for the success of these control procedures.