Electrohydrodynamic (EHD) drying of apple slices

Conventional dryings at high temperatures often produce undesirable changes in the physical-chemical properties of materials. This paper describes the relatively novel technique of electrohydrodynamic (EHD) drying of apple slices, which did not cause any observable product degradation and extensive color changes. Multiple point-to-plate electrodes with AC high voltages, accelerated the initial drying rates to almost 4.5 times over the ambient air drying control. The size of the point electrode, electric field strength, electrode gap, and interelectrode separation were the determinant factors in EHD drying which could be maximized by optimizing these variables. A theoretical consideration showed the principal driving force behind EHD drying to be due to the generation of an electric wind which produced turbulence and thereby enhanced the drying rate of the slices. Ef-ID drying is basically non-thermal and convective, and hence could provide an advantage to industries involved in manufacturing heat-sensitive materials.