The sorption isotherms of candle nuts, unshelled and shelled kernel samples, were measured at temperatures of 30, 40, 50, and 60 degrees C by a static gravimetric method. The unshelled kernel samples had a higher equilibrium moisture content than shelled kernel samples at all tested conditions. In both samples, hysteresis was pronounced and decreased as the temperature increased. The isosteric heat of desorption, calculated using Clausius-Clapeyron equation, was higher than the isosteric heat of adsorption. The GAB equation gave satisfactory goodness of fit to unshelled kernel samples data with the average of correlation coefficient, r(2), greater than 0.99 and the mean relative deviation, MRD, less than 0.05. (c) 2005 Elsevier Ltd. All rights reserved.