Determination of the water sorption isotherms for cassava flour

Resumo

Cassava is a nourishing food and widely consumed in Brazil in the form of flour. However, it is necessary a more detailed study of the physical-chemical properties of the cassava flour and thus optimize its processing steps such as drying. The objective of this work was to obtain the water sorption isotherms for the cassava flour at different temperatures. For this aim, experiments were carried out using the static method with saturated saline solutions at 30, 40, 60 and 70°C. The data obtained were adjusted on available literature equations using the software MATLAB R2007b. The results indicate that the temperature ranging from 40 to 70°C does not significantly influence the cassava flour equilibrium moisture. It was also found  that both Halsey and Smith's isotherm can be used to predict the cassava flour equilibrium moisture. Furthermore, it was observed a small variation in the equilibrium moisture for water activity ranging from 0 to 0.8.

DOI: http://dx.doi.org/10.14685/rebrapa.v1i2.21