Optimal design of the equipment of thermal treatment of dried egg white by dry heat requires the knowledge of the relevant values of physical properties of this product. The water activity and enthalpy have been measured as functions of temperature and moisture content for desorption process that mimics the real conditions during dry heat processing in pilot hot-rooming equipment. The heat of evaporation was predicted from these data as a function of moisture content of the egg white powder. The enthalpy of the product as a function of temperature during desorption of water from moist egg whites starting from various levels of the moisture content was measured by differential scanning calorimetry (DSC). An example is provided of the use of the data for engineering calculations of simultaneous heat and mass transfer illustrating the value of the data to design engineers. (C) 2007 Elsevier Ltd. All rights reserved.