GALVÃO, I. B.; http://lattes.cnpq.br/3437955242977256; GALVÃO, Israel Buriti.
Resumo:
The present work had as objective to make a study of the continuous and intermittent
drying of fresh and osmotically pre-treated of apple pieces cut in form of parallelepiped,
using both empirical and diffusive models to description of the kinetics of the processes.
For the diffusion model, thermo-physical parameters and variable dimensions were
assumed. A bibliographic review was done on the subject, details of the materials and
methods used, the validation and testing of the in three-dimensional FORTRAN solver
developed using the finite volume method, with a fully implicit formulation.
Experiments were done using a freezer shaker incubator for the osmotic dehydration in
order to prepare the samples for subsequent drying. The drying was realized in an oven
with air circulation at temperatures of 50 and 70 ° C, for continuous and intermittent
drying of the apples (with intermittent ratio of 2/3 and tempering periods of 30 min, 60
min and 120 min for the fresh fruits, and tempers of 20 min and 30 min for osmotically
pretreated fruits). The results of drying kinetics, estimates of parameters related to the
fruits studied, were compatible with the literature. At the temperatures and the
tempering periods used, they significantly influenced the kinetics of the moisture
content, as well as the values of the process parameters determined by optimization for
all configurations. Here also is shown the impact of intermittent drying on the energy
saving and how the intermittent drying change for the better the product quallity is
shown.