Abstract: A system for conditioning grain in a sealed container through the removal of liquid from a bushel of grain by sequentially evacuating high relative humidity air from the sealed container and thereafter allowing dry environmental air to reenter the sealed container. A sensor in the sealed container detects the relative humidity therein and supplies a controller with a signal to operate a pump which evacuates high relative humidity air from the sealed container. Thereafter, a pressure sensor detects a vacuum in the sealed container and supplies the controller with a signal which terminates the operation of the pump to allow dry environmental air to reenter the sealed container. The replacement of high relative humidity air with dry environmental air continues until the liquid content per bushel of grain is at a desired level.