Soybeans contribute to healthy nutrition because of the high proportion and quality of proteins Its oil content is considerably lower than in peanuts restricting energy intake To produce a whole soybean snack four type of samples were processed by first increasing the water content and then reducing it by hot-air fluidisation moistened-dried at 60 degrees C (MD) soaked-dried at 60 degrees C (SD) soaked and dried-toasted at 140 degrees C (SDT) and soaked-cooked and dried-toasted at 140 degrees C (SCDT) A semi theoretical model was proposed to describe volume and density as a function of moisture during fluidisation An equilibrium shrinkage coefficient a was determined Volume expansion achieved by increasing the moisture content was not totally lost during fluidisation allowing for lighter products whose density decreased with the reduction in moisture As the overall treatment was more severe (SCDT > SDT > SD > MD) shrinkage coefficients increased up to 0 75 The SCDT sample became crispy and glassy after cooling (C) 2010 Elsevier Ltd All rights reserved