الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The aim of this study is to investigate a new drying method that depend on absorbing the moisture from the air using some chemical materials named desiccants. These materials have a great affinity for moisture; so when the wet air passes through the desiccants it becomes less wet and its temperature becomes a little higher ranging from 2 to 4°C. Then the dehydrated air was used in drying garlic slices. The experiments were done in two stages; the initial experiments were with no load (without plants in the drying chamber) on purpose of choosing the best treatment that provides high dehydrated air. Three forced air velocities were used (2.0, 4.50 and 7.0 m/s) in combination with three desiccant materials and four configurations of them. The used desiccants were sulfuric acid conc., calcium chloride anhydrous and silica gel. The best treatment for dehydrating the air was when air passes in succession through 4 flasks of 500 ml H2SO4, 500 g CaCl2, 500 ml H2SO4 and 500 g SiO2 with the lowest velocity (2.0 m/s). The declination of moisture was from 56.77% to 18.2%. In the second stage we used oven dryer at 70 °C and Desiccant Drying System (DDS) with the best treatment in drying garlic with slices thickness 3 mm. Three levels of loading were also used 1.15 Kg/m², 2.3 Kg/m² and 4.6 Kg/m². The quality attributes of the fresh and dehydrated garlic slices were evaluated for color and oil content. The results revealed that using the DDS method provides a good quality dehydrated garlic slices with higher oil content and lower color change. It also involved low energy consumption and high drying efficiency compared to the slices dried by using oven drying method.