Abstract:
In this research, rehydration behavior of dried fig
s was studied at different temperatures
(25, 60, 70, 80, and 90
°
°°
°
C). The rehydration kinetic was examined using the
four most
frequently used empirical models, namely, Weibull,
Peleg, first-order, and exponential
association models. The Weibull model gave the high
est coefficient of determination (R
2
)
and the lowest values of root mean square error (RM
SE), sum of squared error (SEE), and
chi-square (
χ
2
) was considered the best. In all models examined,
the equilibrium moisture
content showed statistically significant difference
s as compared to the rehydration
temperature. The temperature dependence of kinetic
constants was described in terms of
Arrhenius relationship. The average activation ener
gy for the four models was 24.362 kJ
mol
-1
. During the rehydration process hardness of dried
figs decreased, which was further
confirmed by microscopic evaluation. Scanning elect
ron microscopy (SEM) images of
rehydrated figs indicated porous structure proposin
g the presence of free water.
Keywords
: Kinetic model, Moisture content, Texture, Water a
bsorption.