A process for washing a substrate. The process involves providing a detergent composition that includes a surfactant and an antifoam. The antifoam comprises a hydrophobic fluid having a surface tension of at least 27 mN/m and less than 40 mN/m and a finely divided solid hydrophobic filler dispersed in the hydrophobic fluid. The process further involves washing the substrate in an aqueous medium with the detergent composition. The antifoam does not affect foaming during the washing step. During the washing step, the detergent composition is applied to the substrate. The process further involves rinsing the substrate with the applied detergent composition with water, whereby foaming during the rinsing step is inhibited.