Experimental Investigation of Ginger Drying Using Hybrid Solar Dryer

Ginger is widely used as a traditional medicine for several diseases and has gained more attention due to how healthy and safe it is. Freshly harvested gingers have high moisture content and may cause product deterioration if treated incorrectly. Most ginger farmers still implement the traditional drying method, which requires a long drying time and relies heavily on the weather. In this paper, hybrid solar drying method for ginger is introduced. The performance of hybrid solar dryer, thin-layer modeling, and the quality of dried ginger were investigated. Experimental results show that in four hours of drying, only drying at 60 °C can satisfy the maximum moisture content limit of ginger, which is 12 % wet basis. The decreasing value of drying rate over time indicates that drying of ginger mostly takes place in the falling rate period. Page model is found to be the best thin-layer model to describe the behavior of ginger drying. The values of effective diffusivity are in agreement with the generally accepted value. Although the dried gingers have a good quality according to the standards, the efficiency of hybrid solar dryer is lower compared to other drying methods. Therefore, it can be concluded that hybrid solar drying is applicable for ginger due to fast drying process and acceptable quality of dried ginger, although further improvements are required.