Pulsed Electric Field Effect Pretreatment on the Behavior of Microwave-assisted Pomegranate Arils (Punica granatum L.) Hot air Drying

Abstract Pulsed electric field treatment is a new, non-thermal pretreatment method that preserves foods forexcellent sensory, nutritional and long-life quality. In this study, the impact of pulsed electric field pretreatment on drying kinetics and the quality of dried pomegranate arils was evaluated. The pomegranate arils samples were subjected to pulsed electric field treatment at different intensities of the electric field of 0.5, 1 and 1.5 kV/cm with application of exponentialpulses of 700 µsduration followed by Microwave-assisted Hot air drying. the samplesweredried at 50, 60 and 70°C with a drying times varying from 65 to 190 minutes, while, for untreated arils, the drying time was varying from 90 to 250 minutes. The highest water diffusion coefficient of 8.25 × 10− 8 m2/s was calculated for samples subjected to electric field intensity of 1.5 kV/cm and 70°C treatment temperature. The greatest Hardness was 39.35 ± 4.81 N. The pulsed electric field arils treatments resulted in better electroporation ofthe tissues. The Pulsed electric field -treated dried arils had higher red (a*) and yellow (b*) and (L*) values compare to untreated dried arils.These dried arils are characterized by a high content of total polyphenols 3350.28 mg GAE/kg DM and high antioxidant capacity (0.6 mg eqTrolox g− 1).The drying kinetics were modeled by different models. The models that best fit the drying data was Midilli et al., followed by Logarithmic and modified logistic model.