Prediction of Corn Kernel Stress and Breakage Induced by Drying, Tempering, and Cooling

THE purpose of this study is to develop a mathematical methodology to qualify corn kernel breakage caused by drying processes. Stresses, predicted for a viscoelastic sphere with the physical properties of horny endosperm, were calculated as functions of predicted moisture and temperature gradients in the sphere. Combined processes of drying, tempering (holding the grain at elevated temperatures), and cooling were evaluated. The moisture gradients and, to a lesser degree, the temperature gradients were significant in stress development and relaxation. Since the results indicate that the predicted stresses follow the same trends as published experimental results for the breakage susceptibility of corn, the potential exists for this method to be used as a design tool to estimate the extent of kernel stress and breakage caused by a drying process.