Investigation on relaxation properties of maize kernels based on the multicomponent structure

Abstract

The damage to maize (Zea mays) during processing is closely related to its viscoelastic properties, but the viscoelastic properties of the components of the maize kernel are unknown. This work aimed to measure the stress relaxation of components, evaluate the relaxation behavior, and observe the microstructure for interpreting relaxation properties. It was found that the stress relaxation curves of the components shifted downward with increasing moisture content. The two-element Maxwell model could successfully express the stress relaxation curves. There was a decreasing trend in the model parameters of the components as moisture content increased. The differences in the degree of the elastic behavior would result in a difference in the residual stress percentage and relaxation rate, which could be better interpreted by the microstructure analysis. The results could help optimize maize processing strategies to maintain product quality.