Fluidisation velocities during processing of whole soybean snack

► Raw soybeans were soaked, cooked and dried-toasted at 140 °C by the fluidisation technique to impart a uniform treatment. ► The change in soybean geometric characteristics during drying-toasting were assessed by image-analysis. ► The coefficients of the Ergun-equation, and the minimum and operating fluidisation velocities (Vmf, Vf) were determined along drying-toasting. ► Values required of Vmf and Vf decrease with time during drying-toasting. Correlations are provided, which are useful for process automation.