The drying rate of electrohydrodynamic (EHD) drying was influenced by drying voltage and needle gap. In this article, EHD dried potato slices' moisture content, appearance, microstructure morphology, rehydration ratio and soluble reducing sugar contain, material loss in rehydration process and energy consumption were studied. ANOVA indicated that the drying voltage and needle gap reached extremely significant level on rehydration ratio, but no significant effect on soluble reducing sugar contain; furthermore, there was material loss of EHD drying potato slices in rehydration process, there was a significant level of drying voltage in material loss of rehydration process and energy consumption in EHD drying process. No distinctly difference was observed between the dried potato colors under different conditions, however, the drying condition of high voltage and 4 cm needle gap caused more membrane perforation by scanning electron microscope observing. Through analysis and comparison, the optimal drying technological parameter is 20 kV × 4 cm.
Practical applications
In this article, the optimum technological conditions of potato drying are crystallized, which provides a reference for the design and optimization of drying equipment. At the same time, this article suggests that in the rehydration process, products of EHD drying have different degrees of nutrient loss, which is very important for the further study of EHD drying