Drying Kinetics of Curcuma xanthorrhiza Roxb.
Curcuma xanthorrhiza Roxb. (giant curcuma) is one of herbal plants which is easily found in tropical region such as in Indonesia and has been widely used for medical purposes. This plant has been intensively used as the main ingredients of traditional medicines due to its potent healing power. Giant curcuma is generally dried using a conventional way under the sun prior to use. This method was less controlled, thus leading to poorer quality of products. Drying in a controlled batch dryer could improve product quality in overall. This experiment aimed to study the drying kinetics of giant curcuma using a laboratory designed batch dryer. Drying temperatures were varied between 40°C to 60°C. Samples were also dried in the oven at corresponding temperatures as the control. The drying was conducted until approximately 11 % dry basis moisture content inside the samples was achieved. In general, the drying time of giant curcuma were shorter when the temperatures were increased. This was also confirmed by Page’s Model whereby drying rate constants increased four times both in the batch dryer as well as in the oven when the drying temperatures were increased from 40°C to 60°C.
 Pramono S. Kontribusi bahan obat alam dalam mengatasi krisis bahan obat di Indonesia [Contribution of herbal medicines for combating medicine crises in Indonesia]. Jurnal Bahan Alam Indonesia 2002;1(1):18–20. [in Bahasa Indonesia]
 Republik Indonesia. Keputusan Menteri Kesehatan Republik Indonesia nomor: 661/IMENKES/SK/VII/1994 tentang persyaratan obat tradisional. [Decree of the Ministry of Health Republic of Indonesia Number: 661/MENKES/SK/VII/1994 regarding the prerequisites of traditional medicines]. Jakarta: Menteri Kesehatan RI; 1994. [in Bahasa Indonesia]
 Mahendra B. 13 jenis tanaman obat ampuh [13 types of potent medicinal herbal plants]. Jakarta: Penebar Swadaya; 2005. p. 144. [in Bahasa Indonesia].
 Mohamed LA, Kouhila M, Lahsasni S, Jamali A, Idlimam A, Rhazi M, et al. Equilibrium moisture content and heat of sorption of Gelidium sesquipedale. Journal of Stored Products Research 2005;41:199–209.
 Geankopolis, CJ. Transport process and separation process principles. New Jersey: Prentice Hall; 2003. p.705.
 Ademiluyi T, Abowei MFN. Theoretical model for predicting moisture ratio during drying of spherical particles in a rotary dryer. Modelling and Simulation in Engineering 2013;2013(4):1–7.
 Tarigan E, Prateepchaikul G, Yamsaengsung R, Sirichote A, Tekasakul P. Drying characteristic of unshelled kernels of candle nuts. Journal of Food Engineering 2007;79(3);828–833.
 Jabeen R, Aijaz T, Gul K. Drying kinetics of potato using a self-designed cabinet dryer. Cogent Food & Agriculture 2015;1(1):1–5.