Energy consumption and colour characteristics of nettle leaves during microwave, vacuum and convective drying
Date
2007-04
Authors
Journal Title
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Volume Title
Publisher
Academic Press Elsevier Science
Abstract
Nettle leaves (Urtica dioica L.) were dried from an initial moisture content of 4.41 to 0.1 (dry basis) by involving microwave, convective and vacuum drying, respectively. Energy consumption and colony parameters for the nettle leaves were compared at these different drying conditions. In particular, the experiments were carried out at four different microwave power levels (500, 650, 750 and 850 W) and air temperatures (50, 75, 100 and 125 degrees C) to investigate the effect of these factors on the microwave and convective drying, respectively. Instead, under vacuum drying conditions both the influence of vacuum (20 and 50 mm [Hg]) and drying temperature (50 and 75 degrees C) were considered. Drying periods ranged from 4 to 6, 30 to 120 and 35 to 65 min for microwave, convective and vacuum drying, respectively. The semi-empirical Page's equation was able to reproduce the experimental drying curves at all operating conditions under microwave, convective and vacuum drying. The optimum method with respect to the drying period, colour and energy consumption was the microwave drying at 850 W.
Description
Keywords
Urtica, Hot-air, Dehydration, Quality, Combination, Kinetics, Carrots, Urtica dioica, Vacuum drying, Convective drying, Plants (botany), Color parameters, Microwave drying, Color, Drying, Energy utilization, Microwaves, Moisture
Citation
Alibaş, İ. (2007). "Energy consumption and colour characteristics of nettle leaves during microwave, vacuum and convective drying". Biosystems Engineering, 96(4), 495-502.