Calor isostérico de dessorção para os grãos de arroz em casca.

Abstract

The objective of this work was to determine the desorption isosteric heat values for rough rice of Urucuia variety in function of moisture content. Rough rice grains with initial moisture content of 0.30 d.b. were used. The determination of the desorption isosteric heat was based on the thermodynamic relationship of Clausius Clapeyron in function of neperian logarithm of the water activity by the inverse of the absolute temperature obtained from the sorption isotherm of the product. For calculating the integral desorption isoteric heat it was added the free water vaporization latent heat value to the liquid desorption isoteric heat values. Based on the obtained results, it can be observed that, reducing the moisture content occurs the increase the energy necessary for removing the water from de product, represented by the integral desorption isosteric heat values and its values for rough rice grains in the 12 to 19% d.b. moisture content range varied from 3860 to 2712 kJ.kg-1.