TITLE:
Cassava slices drying by using a combined hot-air single-plane microwave dryer
AUTHORS:
Patomsok Wilaipon
KEYWORDS:
Microwave Drying; Cassava; Drying
JOURNAL NAME:
Journal of Agricultural Chemistry and Environment,
Vol.3 No.1B,
January
16,
2014
ABSTRACT: Characteristics of cassava
drying were investigated by using a microwave hot-air drying system. Two
waveguides were installed on a single plane of the microwave cavity. The drying
experiments were carried out at two levels of sample surface temperature
set-points, 70℃ and 80℃respectively. Cassava (Rayong-9) with 2.5 kg weight
and 61% moisture content on wet basis was dried in the dryer for about 300 - 340
minutes until the final values of moisture content of about 20% db were
achieved. It was found that the drying time decreased with an increase in
sample-surface temperature set point. Approximately 87% of the moisture was
removed during the drying period. It was found that there was a rapid decrease
in moisture ratio values followed by the gradual decline period in all experiments.
With regard to drying kinetics, 5 commonly used mathematical models were examined
with the experimental data. It was found that Page’s and diffusion models
provided a good agreement between the experimental and predicted moisture ratio
values for all temperature set-points. The regression results indicated that
highest values of coefficient of determination and adjusted coefficient of
determination as well as lowest value of standard error of estimation were
reported for the case of Page’s model at 80℃temperature set-point.