In most cases, the raw materials delivered to the mills are not pure grains. Prior to their processing, foreign materials and other contaminants introduced during the harvest, transport and storage of the grain must be removed. The removal of such impurities guarantees the quality of the end products, by reducing ash content, specks, and factors influencing odor and flavor. Additionally, machine wear is reduced and their lifespan increased. Bühler grain-cleaning machines separate defects from grains with maximal precision on the basis of variable physical properties: size, magnetic response, equilibrium velocity, density, length, shape, firmness and color. Because of this, the Bühler Sortex color sorter continues to gain increasing relevance. An effective and consistent means of regulating the grains' moisture levels is an important follow-up to their cleaning. For this, Bühler offers systems for the automatic regulation of moisture levels, comprised of moisture level measurement, calculation of flow rates, water dispensation and its distribution over the grain surface.