In the production of apple juice, a large amount of apple pomace is produced, which can be used as a flavoring agent in animal feed or in the pharmaceutical industry. In order to be able to store pomace in silos, complex drying is required. The RGI sensor measures the residual moisture of the pomace in the dryer in real time. The sensor is integrated into a chute on which the pomace slides. Based on precise measurements, the target humidity can be precisely achieved by controlling the dryer in an optimal and energy-efficient manner.