Influence of temperature, ultrasound, and variety on moisture diffusivity and thermodynamic properties of some durum wheat varieties during hydration

Abstract

This study covers the effect of temperature, ultrasound, and variety on moisture diffusivity and thermodynamic properties of durum wheat varieties during hydration. The process was performed at hydration temperatures of 25, 35, 45, and 55°C during conventional and ultrasound-assisted soaking. The Fick’s diffusion model fitted the experimental data satisfactorily with average coefficient of determination of 0.9946, root mean square error (%, d.b) of 0.0296, Chi-square of 0.0013, and relative mean error (%) of 0.0205, respectively. Deff of wheat varieties during hydration process increased with the ultrasound treatment and temperature increase. Activation energy of wheat varieties decreased with the ultrasound (40 kHz, 200 W) treatment. Increase in Gibbs free energy and negative values of enthalpy and entropy changes with increasing temperature and ultrasonication process confirming the effect of temperature and ultrasound on Deff of wheat varieties during hydration process. Novelty impact statement The results of this investigation can assist wheat products industry in understanding heat and mass transfer phenomena during ultrasound-assisted hydration process of different wheat varieties in tempering, cooking, milling, fermentation, formulation of meals, and storage processes. The results of this study can also be useful in optimizing ultrasound-assisted hydration process and improving the thermodynamic properties of different wheat varieties. New derived generalized hydration equations can be useful for temperature and time-dependent moisture content detection during ultrasound-assisted and conventional hydration processes of wheat varieties.