Determination and Modeling of Thermophysical and Transport Properties of Tropical Pulps

The objective of this work was to determine the thermophysical and transport properties of Hancornia speciosa G. (“mangaba”), Annona muricata L. (“graviola”), Eugenia uniflora Berg (“pitanga”) pulps. The following properties were evaluated: thermal diffusivity, thermal conductivity, heat capacity, density and coefficient of thermal expansion. Rheological properties were determined and adjusted to three models. The effect of temperature on the rheological behavior was also evaluated. The pulps were further characterized in relation to humidity, oBrix, water activity, surface tension, pH and total acidity. The results indicated agreement with literature in relation to thermophysical and transport properties, and the pulps presented a pseudoplastic behavior. Temperature influenced the pulps properties in different aspects: higher effect on the coefficient of thermal expansion of mangaba pulp, higher effect on the rheological behavior of pitanga pulp. The results presented an important advance for the knowledge of food fluids, being necessary for the processing of these materials.