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Drying characteristics of garlic (Allium sativum L) slices in a convective hot air dryer


The effects of drying temperatures on the drying kinetics of garlic slices were investigated using a cabinet-type dryer. The experimental drying data were fitted best to the Page and Modified Page models apart from other theoretical models to predict the drying kinetics. The effective moisture diffusivities varied from 4.214 × 10−10 to 2.221 × 10−10 m2 s−1 over the temperature range studied, and activation energy was 30.582 kJ mol−1.

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a, b, c, n :

Constants of models

k, k 0 , k 1 :

Rate constants in models, h−1


Moisture ratio

D eff :

Effective diffusivity (m2 s−1)

D 0 :

Pre-exponential factor of the Arrhenius equation (m2 s−1)

E a :

Activation energy (kJ mol−1)

L :

Half-thickness of the slab in samples, m

Mt :

Moisture content, g water g−1 dry matter

M e :

Equilibrium moisture content, g water g−1 dry matter

M 0 :

Initial moisture content, g water g−1 dry matter

N :

Number of observations

n :

Positive integer, constant

R 2 :

Correlation coefficient


Root mean square error

T :

Temperature, °C

t :

Drying time, min

χ 2 :

Reduced Chi-square

z :

Number of constants in models


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Correspondence to Yahya Tulek.

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Demiray, E., Tulek, Y. Drying characteristics of garlic (Allium sativum L) slices in a convective hot air dryer. Heat Mass Transfer 50, 779–786 (2014).

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  • Root Mean Square Error
  • Equilibrium Moisture Content
  • Initial Moisture Content
  • Moisture Ratio
  • Final Moisture Content