EFFECT OF DRYING METHODS ON MOISTURE SORPTION ISOTHERMS OF FUFU AT THREE TEMPERATURES

Moisture sorption characteristics for dried fufu using three drying methods at 25°C, 32°C and 45°C were determined experimentally for water activity ranging from 0.11 to 0.96. At a given temperature and water activity, the rotary dried fufu had the highest equilibrium moisture content while the sun dried had the lowest. Four linear and four nonlinear sorption models were used to analyze the data. The linear GAB model showed the best fit while the nonlinear Bradley model was the best over the whole range of water activity in their respective groups. Also estimates of the net isosteric heats of sorption and their dependence on moisture content were presented for each product.