Journal of Food Engineering, Vol.246, 153-159, 2019
Wheat hydration process intensification by periodic operation
Periodic operation has emerged to increase process performance focused on imposing a transient operating regime, however, it has not been employed in industrial grain hydration yet. Thus, periodic operation for wheat grains hydration process with temperature oscillation as a single manipulated variable was investigated. Periodic hydration experiments were performed considering the temperatures of isothermal hydration, with 10 degrees C and 20 degrees C amplitude. In order to compare the performance of periodic with isothermal operation, hydration experiments were carried out at three mean temperatures: 22 degrees C, 30 degrees C and 40 degrees C. Kinetic models were studied, among them the generalized diffusion model presented the best fit with a maximum deviation of 7%. The hydration at 30 degrees C and 40 degrees C with 20 degrees C amplitude intensified the process, with increase in rate mass transfer leading to a 40% reduction in process time. This study proves that periodic operation with temperature oscillation is a highly promising strategy for hydration process intensification.