PROBLEM TO BE SOLVED: To accurately grasp a dried state of grain by measuring a moisture gradient in grain. SOLUTION: Moisture distrubition in grain is measured by electromagnetic waves and moisture gradientsθ1 ,θ2 calculated according to the straight lines 1, 2 connecting the ends E1 , E2 of grain on an arbitrary measuring line and the bottom value B of an approximate curve. If drying control is performed by accurately grasping a dried state of grain on the basis of the moisture gradients, grain can be continuously dried without generating checked grain and a drying time can be shortened.
