The objective of this work is to contribute to the study of starch products in particular Dioscorea cayenensis, Colocasia esculenta and Ipomoea batatas by the characterization and the modeling of their kinetics of convectif drying to the drying oven. The convectif drying of the samples of thickness 4 and 14 mm was carried out at temperatures of 50, 60 and 70 °C. The modeling of the kinetics of drying was carried out with the model of Henderson and Pabbis, the model of Page, the model of Newton and the model of Midilli. The results obtained show that the kinetics of drying of Dioscorea cayenensis, Colocasia esculenta and Ipomoea batatas present two (02) phases. It is of the phase of temperature setting and the phase at decreasing speed. The reduction the thickness of the product from 14 to 4 mm makes it possible to lower the energy barrier (energy of activation) from 19.43 to 10.68 kJ. mol -1 from 35.33 to 11.52 kJ. mol -1 and from 11.08 to 5.77 kJ. mol -1 respectively during the drying of Dioscorea cayenensis (DC), Colocasia esculenta (EC) and Ipomoea batatas(IB). Conversely, the increase the thickness from 4 to 14 mm raises the coefficients of effective diffusion of 8.0 2 ×10 -10 with 3.14×10 -9 m 2 s -1(DC.), of 4.38×10 -8with 2.78×10 -7m 2 s -1 (EC) and of 1.29×10 -7 with 9.53×10 -7 m 2 s -1 (IB) during drying with 70°C. Among does the four (04) models tested, the model of Midilli describe better the kinetics of drying of these three starch products some is the species with the values of coefficient of determination (R2) reduced ki-square (χ2) and the square root of the average error quadratic (RMSE) which vary respectively from 0.99921 = R 2 = 0.99952 of 0.000029 = χ2= 0.0 00071 and of 0.00662 = RMSE = 0.00840.
