Convective air, microwave, and combined drying of potato pre-treated by pulsed electric fields

摘要

The effects of pulsed electric field (PEF) treatment on drying of potato have been investigated. The convective air (CA) (T = 50 degrees C), microwave (MW), and combined (CA + MW or MW + CA) drying was applied. The drying curves, progression of temperature inside samples, microstructure, and capillary imbibition capacity of untreated (U) and PEF treated samples were compared. The PEF treatment noticeably affected the CA and MW drying characteristics and structure of dried samples. It reflected impact of electroporation on the heat and mass transfer processes during the different drying periods. The different progressions of temperatures inside U and PEF samples for the MW mode of drying were revealed. The highest and smallest rehydrations were observed for the U samples for individual CA and MW modes of drying, respectively. The observed behavior was explained accounting for the absence of starch gelatinization for the CA mode of drying and presence of it for the MW mode of drying.