Estimation of the Moisture Diffusivity and Activation Energy in Thin Layer Drying of Ginger Slices

In the present work, the effective moisture diffusivity and activation energy were calculated using an infinite series solution of Fick-s diffusion equation. The results showed that increasing drying temperature accelerated the drying process. All drying experiments had only falling rate period. The average effective moisture diffusivity values varied from 2.807x10-10 to 6.977x10-10m2 s_1 over the temperature and velocity range. The temperature dependence of the effective moisture diffusivity for the thin layer drying of the ginger slices was satisfactorily described by an Arrhenius-type relationship with activation energy values of 19.313- 22.722 kJ.mol-1 within 40–70 °C and 0.8-3 ms-1 temperature range.

Authors:

• Ebru Kavak Akpinar
• Seda Toraman

Keywords:

• Ginger
• Drying
• Activation energy
• Moisture diffusivity.

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