ALMEIDA, R. D.; http://lattes.cnpq.br/4031822293863036; ALMEIDA, Renata Duarte.
Resumen:
This research was conducted in order to study the kinetics of osmotic dehydration and drying
processes used for the preparation of dried banana Pacovan and evaluate the processed product
for several aspects such as the chemical, physico-chemical and texture, depending on the process
variables, temperature and sucrose concentration. The osmotic dehydration process was carried
out with three concentrations of sucrose (40, 55 and 70ºBrix ) and three temperatures (50, 60 and
70ºC). From osmotic dehydration resulted 9 products, which were subjected to a complement
drying at three temperatures (40, 50 and 60ºC) in a fruit dehydrator with trays and without air
circulation. Data from osmotic dehydration and drying were adjusted to three models: Fick ,
Page and Cavalcanti Mata, using nonlinear regressions and the Statistica 8.0 software; the
analysis of water loss and solid gain by osmotic dehydration, was made through analysis of
variance, ANOVA, with comparison of averages by the Tukey Test. The products resulting from
this process were subjected to chemical and physico-chemical testing (water content, acidity,
reducing sugars, pH, total soluble solids, ash, water activity) according to the methodology of the
Adolfo Lutz Institute; minerals content ( K , Ca , P , Mg , Fe ), were determined using X-ray
spectrometry and texture evaluation using a texturometer TAXTplus performed through rupture
of fibers and strength tests. Among the key findings it is concluded that: the sucrose
concentration of the osmotic solution, process temperature as well as the interaction between
these two factors exert influence on water loss and solid gain in the dehydration process; the
model that best represents the experimental data for osmotic dehydration of banana Pacovan is
the Page, with coefficients of determination greater than 90%, the diffusion coefficients
calculated by the Fick model for osmotic dehydration, are between 1,692 x 10-11 and 8,692 x 10-
11 m2.s-1 for dehydrated bananas at 50ºC in 40oBrix solution and 70ºC in 70oBrix solution,
respectively; in complement drying, all tested models satisfactorily represent the experimental
data: the diffusion coefficients calculated by the Fick model to complement drying were between
3.49 x 10-10, for the dehydrated banana in 40oBrix solution at a temperature of 50ºC, with
complement drying at 40ºC, and 4,38 x 10-8 for the dehydrated banana in 70ºBrix solution at a
temperature of 70oC with complement drying at 60ºC; acidity, reducing sugars, total soluble
solids and ash content in the osmotic dehydration increased with increasing sucrose
concentration; the minerals contente present in greater quantities in processed banana are
potassium, calcium, manganese, phosphorus and iron; bananas treated osmotically require
greater effort for fiber breakage as it increases the solids content of the desiccant solution in the
osmotic dehydration.