This work compares the drying behavior exhibited by in natura and by osmotic dehydrated pears, The dryer was a convective vertical tray dryer. The drying was analyzed in terms of effective diffusivity and drying rates. The effective diffusivity varied from 1.59 x 10(-10) to 7.64 x 10(-10) m(2)/s for in natura pear and from 1.87 x 10(-10) to 8.12 x 10(-10)) m(2)/s for the pears after osmotic dehydration. In the case of moisture content below 1.0 kg(w)/kg(dm), the drying rates only depends on temperature, as internal resistance to moisture transfer prevails. (C) 2002 Elsevier Science Ltd. All rights reserved.