Drying of food products is a common practice in Nepali household to preserve perishable food products for future consumption and sometimes for economic purpose. The most commonly used method for drying is under the open sun. However, open sun drying is slow, has no quality control and has risk of contamination creating potential health hazard. An alternative process of drying results to healthy dried food products for family consumption and for captivating food processing.
In solar dryer the black painted tray in the solar dyer which is oriented to south a tilt equals to latitude absorbs sunlight effectively and converts it into heat. The damp air escapes through the upper outlets and the fresh air enters through the lower inlets in the dryer. The moisture content of food is decreased more quickly than in open air. Size and shape of dryer depends on quantity and type of food to be dried and domestic and commercial use.