Techniques for large-scale production of microbial products. It must both provide an optimum environment for the microbial synthesis of the desired product and be economically feasible on a large scale.
They can be divided into surface (emersion) and submersion techniques. The latter may be run in batch, fed batch, continuous reactors
In the surface techniques, the microorganisms are cultivated on the surface of a liquid or solid substrate. These techniques are very complicated and rarely used in industry