Thin Layer Drying Kinetics of Turmeric using Hot Air Dryer

DOI: 10.14416/


  • Parichat Ratmanee Department of Food Science and Technology, Faculty of Agricultural Technology, Rajabhat Mahasarakham University
  • Sutida Phitakwinai Department of Mechanical Engineering, Faculty of Industrial Education, Rajamangala University of Technology Suvarnabhumi
  • Wanich Nilnont Department of Mechanical Engineering, Faculty of Engineering and Architecture, Rajamangala University of Technology Suvarnabhumi
  • Wutthikrai Buakaew Department of Mechatronics Engineering, Faculty of Engineering, Rajamangala University of Technology Rattanakosin


Turmeric, Drying kinetics, Effective moisture diffusivity, Hot air dryer


This research aims to study the drying kinetics of turmeric using a hot air dryer to investigate the effective moisture diffusivity. The drying temperatures of turmeric are 40, 50, 60 and 70 oC. The air velocity is approximately 1 m/s. The results showed that the effective moisture diffusivity of turmeric was between 3.28 ×10-11 to 1.67 × 10-10 m2/s. Color parameters L* (lightness), a* (redness/greenness) and b* (yellowness/blueness) were used to estimate color changes during drying.  L*, a* and b* values of dried turmeric decreased as the drying temperature increased. In addition, the curcumin content of fresh turmeric and dried turmeric, which were dried at various temperatures, were analyzed. It was found that affected the reduction of the curcumin content. In this experiment, the curcumin content of dried turmeric is still within the standard of herbal medicine.


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บทความวิจัย (Research article)