ABSTRACT

Introduction ........................................................................................................ 519

Materials and Methods ..................................................................................... 520

Results and Discussion ..................................................................................... 521

Conclusions......................................................................................................... 523

Acknowledgments ............................................................................................. 523

References ........................................................................................................... 523

Fractal analysis could be an alternative tool for describing the shape and

microstructure of dehydrated products and for evaluating structural

changes during drying processes (Belloutio et al., 1997; Pedreschi and

Aguilera, 2001; Quevedo et al., 2002; Chanona-Pe

´

rez et al., 2003; Alamilla-

Beltra

´

n et al., 2005). The microstructural changes of materials with drying

conditions can be correlated to fractal analysis parameters, and may help to

improve the product quality in the manufacture and processing of foods.

Aspects related to moisture transport in biological models could be

explained by fractal analysis, thus allowing the finding of a descriptive

model for the drying of spheres and powders based on the different

correlations observed between morphology evolution and apparent fractal

dimension. The objective of this work was to study morphology and

microstructure development, including evaluation of particle size and

parameters related to transport phenomena such as drying kinetics and

effective diffusion coefficients during the air drying of spheres and the spray

drying of particles.