To clean a coffee grinder, unplug it, remove the hopper and grind chamber, using a small brush,  thoroughly clean the burrs and grind chute, removing any coffee grounds and oil buildup; If you like, you can run a small amount of uncooked rice through the grinder to further clean the internal parts, and then wipe down the exterior with a damp cloth; always consult your grinder’s manual for specific cleaning instructions. For a manual coffee grinder, add 1/4 cup of sugar and grind for 10 seconds. The sugar will absorb any oils from the grinder but won’t impair the taste of the next thing you grind.