On the Intermittent Drying of an Agricultural Product

A mechanistic model has been employed to demonstrate the significant advantages of intermittent drying of an agricultural product. The model incorporates both liquid and vapour migration as well as heat transfer in a food material. Analyses of predicted results show good agreement between the simulation model and experimental values within 7.4%. The model shows tempering of the product and increased surface moisture content when the air temperature was switched from the ‘on’ period to the ‘off’ period. The time-evolution of the product surface temperature and moisture has been investigated for both constant and intermittent drying schemes. Comparison of the drying front due to intermittent and constant drying is also made.