Scale-up strategies for solid state fermentation systems.

Scale-up strategies for solid state fermentation (SSF) systems are reviewed under the following headings: The significance of scale-up; Peculiarities of scale-up exercises; Scale-up stages; Problems associated with scale-up (variations in biomass formed, large scale inoculum development, medium sterilization, aeration, agitation, heat removal, moisture content of the solids, pH control, contamination control, heterogeneity, downstream processing, waste management, solid handling); Scale-up criteria for SmF (submerged fermentation) processes (diversity and magnitude, practicability for SmF processes, applicability to SSF system); Scale-up methods used in SSF systems (the scaling-down approach, trial and error approach, maintenance of geometric similarity, maintenance of constant heat and water balances); and Need for developing more scale-up strategies.