Dry weight model, capacitance and metabolic data as indicators of fungal biomass growth in solid state fermentation

Developing improved industrial bioprocesses has been a driver for the growing research attention to solid state fermentation, in particular involving filamentous fungi. Accurate description of fungal growth in these systems is crucial and certainly needed to enable optimal deployment of subsequent engineering work. This manuscript proposes a model based on total dry weight measurement to describe biomass growth for Aspergillus awamori on wheat grains in two systems: Petri dishes and a 1L packed bed bioreactor. The proposed dry weight model can be used not only for identifying growth phases of the fungus but also to calculate key growth parameters such as specific growth rate and maximum biomass concentration. The use of techniques based on capacitance measurements and on metabolic data were also used in order to estimate fungal growth and to validate the proposed model.