The ability to predict the behavior of fermentation systems enhances the possibility of optimizing their performance. Mathematical equations of model systems represent a tool for this and the most recent advances in computer hardware and software have made the approach more effective than previous simplistic attempts. The current knowledge of biochemical microbial pathways and the experience in optimization of chemical reactors combined with extremely powerful and accessible computers, loaded with easy to use software and mathematical routines, are changing the way processes are being...