Drying Characteristics and Quality of Kiwifruit Slices with/without Osmotic Dehydration under Short- and Medium-Wave Infrared Radiation Drying

摘要

In this paper, short- andmedium-wave infrared radiation (SMIR) drying characteristics of kiwifruit sliceswith- /without osmotic dehydration (OD) were investigated. High fructose corn syrup (HFCS) was selected as the best osmotic solution and coupled with SMIR. Both infrared drying processes with/without OD occurred mainly in the falling rate period. Results indicated that the Logarithmic model and Page model were best in predicting moisture transfer for the kiwifruit slices with and without OD, respectively. The values of effective diffusivity ranged from 4.10×10~(-10) m~2 /s to 9.52×10~(-9) m~2 /s and from 3.10×10~(-10) m~2 /s to 1.16×10~(-8) m~2 /s for kiwifruit slices with and without OD, respectively. During the overall falling rate period, the activation energy value was 29.51 kJ/mol and 27.44 kJ/mol for the osmosed and non-osmosed kiwifruit slices, respectively. As compared with non-OD, OD pre-treatment could improve the drying characteristics, decrease color change and increase the retention ratios of ascorbic acid and chlorophyll.