Study on Drying Turmeric by a Solar Dryer

Abstract

This research aims to study turmeric drying by solar energy. The dimension of dryer was 1×0.8 m², which has 2 systems were a passive system and an active system, compare with tray dryer. The turmeric was prepared in 2 mm of thickness for drying. By no products operation testing found that, an average inside air temperature in dryer were 47.8 ± 3.9°C and 49.0 ± 3.5°C, respectively. So, this temperature was suitable for turmeric drying. From the study of drying time found that the drying time was 7 hours in all types of dryers (2 systems solar dryer, tray dryer), which a moisture content of the product is according to a dried herb standard. The moisture content of dried product was 10.60 ± 0.85, 11.43 ± 0.82 and 11.61 ± 1.07 dry basis, respectively. and a thermal efficiency of drying system was investigated. The passive solar dryer had high thermal efficiency at 8.77 ± 0.22, so that, yield of drying product of all drying types were 20.72 ± 0.04, 25.99 ± 0.63 and 21.50 ± 0.50, respectively. Moreover, a quality of drying product was studied. For aw parameter. The value was less than 0.60 in all drying types and was according to the standard. For a color value found that all four samples of dried turmeric were shades of yellow orange. However, using an active system solar dryer can dry products with color L* and C values are not different from products in the market.