Development and Assessment of a Mix-mode Rack-Type Passive Vegetable/Fruit Solar Dryer

A mix-mode solar dryer which incorporates a flat plate collector into a framed-rack dehydrator glazed with polythene was developed to address the difficulty encountered in drying tomatoes during bumper harvest times in Zaria, Nigeria.The evaluation results of the rack dryer using 10 kg of fresh tomatoes revealed a dry rate of 0.71 kg/hr and drying efficiency of 65.90 % when dehydrating tomatoes from an initial moisture content of 94 (% wb) to a final moisture content of 4.25 (% db).The efficiency of the dryer indicates its suitability for crop drying especially fruits and vegetables, with high moisture contents.This dryer will find great application in households and among operators of restaurants who can dry and store tomatoes hygienically within two days in batches for use during scarce periods.