ABSTRACT
The post-harvest stage of crops aims to minimize losses occuring during storage and commercialization. Drying process are some of the most used methods to minimize those losses. This work aimed at studying the drying kinetics of cinnamon (Cinnamomum zeylanicum), subject to two different drying conditions, one of which in an experimental fixed-bed dryer relying on an ambient air and speed of 0.5 m s−1, and the other with a forced air circulation oven at different temperatures (313.5, 323.15, 333.15 and 343.15 °K). The time required to reach the moisture equilibrium contents was 1.42, 3.0, 6.41, 14.0 and 21 h for drying temperatures of 343.15, 333.15, 323.15, 313.5 and 307.95 ºK, respectively. The Arrhenius equation described the diffusivity’s dependence on temperature, defining the activation energy of 64.77 kJ mol−1. The essential oils of the samples were analyzed through gas chromatography, which identified 23 individual compounds being eugenol the most abundant.
Nomenclature
± | = | approximate |
a, b, c, n | = | Coefficients of the models |
d.b. | = | dry base |
º | = | degree |
D | = | Effective diffusion coefficient |
Df | = | Effective diffusion coefficient |
D0 | = | Arrhenius factor for the drying process |
DF | = | Degrees of freedom of the model |
Ea | = | Activation energy |
HPLC | = | High Performance Liquid Chromatography |
h | = | Drying constants |
k, k0,k1 | = | Drying constants |
ºK | = | degrees kelvin |
kJ/mol | = | kilojoule per mole |
kg | = | kilogram |
m s−1 | = | meter per second |
m | = | meter |
’ | = | minutes |
m2 | = | square meter |
m3 | = | cubic meter |
n | = | Number of terms; |
N | = | Number of experimental observations |
P | = | relative mean error |
% | = | percent |
RX | = | Moisture content ratio |
R | = | Universal gas constant (8.314 kJ kmol−1 K −1) |
R2 | = | coefficient of determination |
S | = | Leaf surface area |
SD | = | standard deviation |
SE | = | estimated mean error |
” | = | seconds |
s | = | south |
t | = | Drying time |
Tabs | = | Absolute temperature |
V | = | Leaf volume |
X* | = | Moisture content, decimal |
X*i | = | Initial moisture, decimal |
X*e | = | Equilibrium moisture |
w | = | west |
Y | = | Experimental value |
Ŷ | = | Value estimated by the model |
π | = | 3,141592 |
Disclosure statement
No potential conflict of interest was reported by the authors.