In considering a particular fermentation there are a number of choices regarding process operation. Typical  initial considerations are listed below. Again, the choices made will depend upon the type of product being manufactured. Submerged liquid culture  vs   Perfusion, immobilised cells, microbial films

Aseptic                vs        Non-sterile
 
Single strain          vs        Mixed culture
 
Aerobic                 vs        Anaerobic
 
Batch/Fed-batch    vs        Continuous
 
Three phase          vs        Four phase

Solid - Cell                       Solid - Cell

Liquid - Medium                Liquid - Broth and hydrocarbon

Gas - Air                         Gas - Air