Kinetic modelling of drying and conversion/degradation of isoflavones during infrared drying of soybean

► Kinetic models of drying and isoflavones changes during soybean drying were developed. ► First-order kinetic models could be used to describe the changes of isoflavones. ► Higher drying temperature led to higher effective moisture diffusivity and rate constant of isoflavones changes. ► Deesterification was the predominant reaction of isoflavones changes during drying. ► The activation energies of degradation were lower than those of inter-conversion of isoflavones.