By applying the transition state theory, enthalpy-entropy compensation was studied for water loss data obtained during deep-fat frying of three kinds of potato chips: control, blanched and dried. Two alternative approaches were used to obtain the isokinetic temperature: enthalpy/entropy relationship and rate factor/activation energy relationship. Values of 385.2 degrees K and 383.7 degrees K were found, respectively. Both values are lower than the harmonic mean temperature which was found to be 400.7 degrees K, meaning that the mechanism of water loss is entropy controlled. (C) 2008 Elsevier Ltd. All rights reserved.