Drying characteristics and quality evaluation of 'Ankara' pear dried by electrohydrodynamic-hot air (EHD) method

Abstract

The fruits are seasonal and usually available at a particular season of the year. The post-harvest processes are applied to ensure that the products are consumed throughout the year. Drying is one of the most important postharvest processes, and the hot air method is generally used. In this study, 'Ankara' pear samples were dried by combining the electrohydrodynamic method, a promising drying technology, with hot air. This study aims to investigate the effects of different air velocity and voltage values on drying time, color, rehydration capacity, and microstructure. In addition, ten mathematical drying models were applied to the experimental results of the drying processes to obtain the model that best explains the drying curves. Two different air velocities (1.5 and 2.5 m/s) and four different voltage values (15, 20, 25, and 30 kV) were used for the drying processes. The process of drying pear products in the shortest time (80 min) was in the application of 30 kV-2.5 m/s. The models that best explain the drying curves of 'Ankara' pear were found to be the Logarithmic and Midilli et al. models. While the highest L* value was observed in the fresh product, the closest value to this value was observed in 15 kV-1.5 m/s applications. Rehydration capacity values of pear samples dried at high voltage values (25 and 30 kV) increased with increasing air velocity. The EHD-hot air method used in this study can be an alternative to conventional drying and can be a viable method in the drying industry by determining the appropriate air velocity and voltage value in order to provide better quality products in a short time.