Several scientific types of research have already been carried out on yam tuber varieties of the Dioscorea family such as Dioscorea Retundata, and Dioscorea Alata. We can mention among others: the determination of sorption isotherms, their isosteric heat, and the drying kinetics. Dioscorea Schimperiana is also a tuber belonging to the same family and is currently a very popular foodstuff in the West Cameroon region. This plant, considered a nutritional element, also has several therapeutic virtues. However, the lack of knowledge of some of its thermophysical properties, especially the water content at equilibrium, is a hindrance to its optimal use. The present study, therefore, focuses on the determination of desorption isotherms, which could be useful for the modeling of a suitable dryer for the drying of Dioscorea Schimperiana. These desorption isotherms are obtained by the static gravimetric method, in the range of relative humidity from 11 to 97% and temperatures of 30°C, 40°C, and 50°C. The Henderson, Harkings and Jura, Halsey, modified Oswin, and GAB models were used for smoothing the experimental points. The isotherms obtained are of type II and characterized by a sigmoidal shape. The best fits were obtained for the GAB and Henderson equations.

Keywords : Dioscorea Schimperiana, water content, the isotherm of desorption, relative humidity, GAB, Henderson