I love using produce wash, which is essentially a detergent for your fruits and veggies. If you can find it, you can make a sudsy bath for the grapes. Let them soak for 5-10 minutes, agitating them occasionally to help loosen any grime, then drain and rinse well under cool running water. If you don’t have produce wash on hand, plain white vinegar can also be used! Add 1 part vinegar to 3 parts water, then soak, agitate, and rinse as described above. Before using, be sure to remove any grapes that have visible damage. Once the skins are broken, the bacteria and pesticides can leach into the fruit and won’t be able to be removed by traditional cleaning methods.