A study on advantages and limitations of ehd drying of food materials

Energy consumption index is one of the most important criteria for judging about new, and emerging drying technologies. Electrohydrodynamic (EHD) drying is a novel method of non-thermal processing. The drying can be carried out using either AC or DC high voltages. The thermodynamic considerations regarding the lowering of temperature under EHD drying include rapid rates of evaporation and exothermic interaction of the electric field with a dielectric material. Multi-point and plate electrode systems are efficient in accelerating drying of agricultural materials. Compared to hot air (convective) drying systems, EHD drying systems offer lower food production costs along with superior quality in terms of physiochemical properties such as color, shrinkage, flavor, and nutrient content. This paper presents briefly the nature of ElectroHydroDynamic (EHD) phenomena, and details on the mechanisms of moisture movement inside the solid and its evaporation at the exposed solid surface during drying of solids. Choosing the data presented in literature, a critical discussion is presented on the advantages and limitations of EHD drying of food materials.