When chopping or blending foods that have a rich, bright, or very dark color, there can be stains left on the plastic of the bowls and the accessories used. In order to help prevent stains it’s important to wash the Control Grip™ parts immediately after use. Even with doing that, the stains can still come about. We recommend filling the bowls with hot soapy water and adding in about 4 tablespoons of lemon juice. These can be set aside to soak for an hour or two or even overnight.