Volume changes of wheat and barley soaked in water were determined utilizing measurements of particle density and bulk density. The effects of moisture content and temperature on the specific volume of the sample were investigated. An empirical equation relating moisture content and temperature to specific volume was derived, and the measured data agreed well with the values calculated from the equation. Within the range of temperatures tested, the coefficient of thermal expansion of the sample was small. Therefore, the specific volume could be considered a linear function of moisture content only. In addition, the specific volume in bulk was related to a quadratic function of moisture content. (c) 2005 Elsevier Ltd. All rights reserved.