Secagem por aspersão da polpa de buriti.

Abstract

This work was developed with aimed of drying buriti pulps in spray dryer and evaluate chemical, physical and physico-chemical characteristics of buriti pulp whole, pulp formulated (emulsions) and powder samples. The emulsions were prepared by mixing the buriti pulp with distilled water (1:1) and adding maltodextrin with three different dextrose equivalent (DE = 10, 14 and 20) and with different concentrations (5, 10 and 15%). The moisture, total solids, soluble solids (°Brix), pH, titratable acidity, ash, density and color were determined in the buriti pulp whole and in the emulsions. The viscosity of emulsions were determined at 30°C. In the spray dryer two types of powder sample were collected according to the place: drying chamber and cyclone. The moisture content, the titratable acidity, ash, density and color of the powder samples were analyzed using the factorial experimental design. The moisture adsorption isotherms at temperatures of 20, 30 and 40 °C were determined only in powder samples collected in the drying chamber of the spray dryer and the GAB, Oswin and Peleg models were fitted the experimental curves. All the emulsions prepared showed a pseudoplastic behavior and there were a tendency to increase the apparent viscosity with increasing maltodextrin concentration. Emulsions tested (DE = 10 and concentrations of 5, 10 and 15% maltodextrin) in the dryer proved to be viable for the production of buriti pulp powder in spray dryer. The powder samples collected in the drying chamber and cyclone showed different characteristics. Among the parameters analyzed for the powder samples found that only the density of the samples collected in the drying chamber, the empirical model of first order obtained was statistically significant and predictive. Most of the moisture adsorption isotherms of powder samples were classified as type I I , and the best fit to the experimental data were obtained using the Peleg model.