Reologia da polpa de figo-da-índia.

Abstract

In this work it was studied, the rheology of cactus pear pulp in a temperature range from 10 to 60°C and in concentrations from 13 to 28°Brix. In the process of obtaining the pulp it was made: selection, wash and disinfection, to peeling, extraction of the pulp, concentration, packaging, freezing and storage in freezer to -20°C. In the physiochemical analyses, was determined pH through a potentiometer, it was determined total soluble solids by refratometric method, insoluble solids in water by Instituto Adolfo Lutz method, the pectin determination it was made by Carre & Haynes method, the determination of total solids and moisture followed the Instituto Adolfo Lutz methodology. The rheologicals readings were made with the use of a viscometer Brookfield RVT model. The experimental data were fitted with Casson, Ostwald-of-Waelle, Vocadlo and Herschel-Bulkley's rheological models, enphasing that, this last one it was adjusted better to the data. All these samples presented behavior non-newtonian of the pseudoplastic type, for the four models. The viscosity it was influenced by the concentration and temperature.