Tarbiat Modares University Journal of Agricultural Science and Technology 1680-7073 20 2 2018 03 01 Effect of Different Drying Conditions on the Mass Transfer Characteristics of Kiwi Slices 249 264 16141 EN H. Darvishi Department of Biosystems Engineering; Faculty of Agriculture, University of Kurdistan, Sanandaj, Islamic Republic of Iran. P. Mohamamdi Department of Biosystems Engineering; Faculty of Agriculture, University of Kurdistan, Sanandaj, Islamic Republic of Iran. M. Azadbakht Department of Biosystems Engineering; Faculty of Water and Soil Engineering, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Islamic Republic of Iran. Z. Farhudi Department of Biosystems Engineering; Faculty of Agriculture, University of Kurdistan, Sanandaj, Islamic Republic of Iran. Journal Article In this study, the influences of drying conditions on the mass transfer characteristics of kiwi slices are investigated using the analytical model proposed by Dincer and Dost. The experiments were conducted at temperature range of 50–80°C with 0.5 m s-1 air velocity for convective drying and in the microwave power range of 200–500W for microwave drying as single layers with sliced thickness of 3, 6, and 9 mm. The results show that the mass transfer characteristics strongly depend on the drying conditions. Through the convective drying method, parameters including moisture diffusivity, mass transfer coefficient, Biot number, and drying time were varying from 0.16-1.45×10-8 m2 s-1, 1.93-4.95×10−7 m s-1, 0.103-0.225, and 90-604 minutes, respectively. In comparison, for microwave drying, they were within the ranges of 0.66-25.60×10-8 m2 s-1, 0.62-5.64×10−5 m s-1, 0.960-1.742, and 4-23.5 minutes, respectively. Results reveal that the activation energy for moisture diffusion is higher than that needed for the convective mass transfer process.

https://jast.modares.ac.ir/article_16141_81b9550f1b1820eca22b1dd083af2b13.pdf