Equilibrium moisture content, mass diffusion coefficients, and densities were collected for wheat flour, shredded wheat, raisins, nonfat dry milk, and freeze-dried apple, turnip, and ground beef at 25 ± 1°C. Flour adsorbing to 0.75 aw had the largest mass diffusion co-efficient, 1.15 × 10−7 m2/hr and raisins had the smallest value of 0.015 × 10-7 m2/hr. Two of the food uroducts. flour desorbing to 0.11 aw, and the freeze-dried turnip, exhibited diffusion coeffcients which were dependent on the moisture content. Most of the foods reached equilibrium within 1 wk based on an objective criterion of no more than a 0.5% dry basis moisture difference over three successive readings at 1 wk interval.