As with all grinders, you first need to disassemble it for easy access to its parts. Tap each part gently to remove excess matter. Then brush all the surfaces with a toothbrush or small paintbrush. Scrape off the stubborn stuff. Next, you should place the parts of the metal grinder in a bowl of isopropyl alcohol to kill off any bacteria and leave to soak. Remove them with tongs then set them aside to cool and dry before reassembling your grinder.