Thermal conductivity of moist wheat bran beds used in solid state fermentations

A mathematical model was introduced to describe the heat transfer behaviour of moist wheat bran beds. Comparison of predicted transient temperature profiles with experimental data collected in a simulated bed was used to evaluate bed thermal conductivity at various conditions. This parameter was correlated with the bed density and moisture content via a mathematical relation. Furthermore, extent of error in thermal conductivity evaluation resulted from neglecting water vapour diffusion was quantified. Results provide useful means to design, analyse, and predict the behaviour of solid state fermenters in a more reliable manner.