Pengaruh Metode Pengeringan terhadap Kinetika, Karakteristik dan Kualitas Temulawak Kering (Curcuma Xanthorrhiza Roxb.) menggunakan Metode Pengeringan Matahari Terbuka, Oven dan Flat Bed Dryer

Abstract

Drying is one of the oldest preservation methods where heat is transferred from the environment to the wet material by convection / conduction / radiation thereby evaporating the water contained in the material. Drying Curcuma xhantorriza roxb aims to extend the shelf life, maintain the active substance content in the ingredients, and facilitate subsequent processing. In this research, Curcuma xhantorriza roxb was dried using the open sun drying method (variations in hot weather, normal weather and cloudy weather with a thickness of 5, 10 and 15 mm). Oven (temperature variations 50, 60 and 70 oC with thicknesses of 5, 10 and 15 mm), and flat bed dryer (FBD) as a comparison of the two methods which are operated at a temperature of 50 oC with a thickness of 5 mm. Next, the drying results will be compared based on the curcuminoid content of dried curcuma xhantorriza roxb. In addition, a study was carried out on changes in the surface morphology of curcuma before and after drying and determined the drying kinetics model from the five models used, namely the diffusion approach, page, two terms, logarithmic and Verma et. al. The results obtained from drying curcuma using the open sun drying method, oven and FBD is dried curcuma with moisture content respectively amounting to 7.35% (wb); 0.92 % (wb); and 9.08% (wb). The time needed to dry curcuma is 30.33 hours (open sun), 12 hours (oven) and 9.33 hours (FBD). Analysis results Spectrophotometer UV-VIS to determine curcuminoid levels in fresh and dried curcuma is 1.36% and 0.36% (Open Sun); 3.22 % and 2.91 % (Oven); 2.64 % and 2.34 % (FBD). The results Analisys used Scanning Electron Microscope (SEM) on fresh and dried curcuma from drying in the open sun (hot weather), oven (50oC) and FBD (50oC) that is, in fresh curcuma you can see that the surface microstructure has many pores and small porosity, whereas in dry curcuma there is a change in surface microstructure causing the pores to close and porosity to increase. The kinetic model that is suitable for describing the drying mechanism in this research is the diffusion approach model for the open sun and oven drying methods, while for the flat bed dryer it is the logarithmic model. The best drying method produced in this research is the oven drying method.