The influence of thin layer convective dehydration parameters on drying
kinetics parameters, chemical composition, and color parameters of carrot
slices were investigated, and corresponding mathematical models were
developed. In the carrot slices, convective dehydration process hot air
temperature and the sample slice thickness were varied, while measured,
calculated, and modeled responses were: time of dehydration, effective
moisture diffusivity, the energy of activation, proteins and cellulose
contents, lightness, redness, and yellowness. The obtained results showed
that varied convective dehydration process parameters statistically
significantly affected all investigated responses except activation energy.
The most efficient drying model with the minimum thickness (3 mm) and the
maximum drying temperature (70 ?C) had the shortest drying time (231 min).
This model had the minimum resistance to mass transfer (the minimum
effective moisture diffusivity, 2.04?10-08 - 7.12?10-08 [m2s-1]), and the
average maximum energy of activation (31.31 kJmol-1). As far as the carrot
slices' chemical composition and color parameters were concerned, the model
with the maximum thickness (9 mm) and the minimum drying temperature (35 ?C)
was the optimal one. This model had the longest dehydration time (934 min),
the maximum resistance to the mass transfer (8.87?10-08 [m2s-1]), the
minimum total protein content (5.26 %), and the darkest color (49.70). The
highest protein content (7.91%) was found for the samples subjected to the
highest drying temperatures and the lowest carrot slice thickness. In
contrast, the process of convective dehydration had led to the lighter,
reddish, and yellowish carrot slices. All developed mathematical models were
statistically significant.
Modeling convective thin-layer drying of carrot slices and quality parameters
