Bioprocessing - Fermentation

Fermentation is the process of breaking down a substance into simpler components to produce specific chemical and/or physical changes in the media. It occurs in vessels called bioreactors (or fermenters), which are designed to maintain an optimal environment for cultivating organic material.

Requirements for an optimal fermentation environment

• Very accurate and gentle, controlled flow to maintain cell integrity.
• Precise handling of feed, acid, base and anti-foam fluids.
• Single-use applicability with zero cross-contamination

Bioprocess engineers need to consider the following factors while choosing the right pump:

• Fluid viscosity

As higher viscosities of fluids create higher forces on a pump, the pump needs to be robust enough, and additionally, equipped with a motor that provides the right level of drag torque.

• Sensitivity of the fluid to shear-forces

Some fluids are very sensitive to shear-forces placed upon them, hence, the right pump should ensure a gentle pumping motion that does not lead to altering the fluid components (i.e. destroying cells in the fluid due to high shear-forces).

• Need for sterility of the fluid path

Since a sterile environment is a crucial factor in determining whether aseptic fermentation is successful, contact of the organic matter with hardware components should be limited to only those parts that follow the highest sanitary standards.

• Accuracy and Precision

Accurate and precise delivery of the organic fluid to the bioreactor is an important aspect of the fermentation process. The achievable accuracy and precision depend largely on the pump technology. In order to achieve as good accuracy and precision as possible, calibration and usage of sensors can help to overcome limitations inherent to certain pump technologies.