How do I clean my coffee grinder?

By Norbert Ahnsorge (Inhaber) · Published · updated

Brush it out every 1–2 weeks to remove old coffee residues and oils. For espresso grinders, use cleaning pellets. Never clean the burrs with water — rust and clumping would be the result.

Why that is

Coffee leaves residues in the grinder after every use: fine coffee grounds, oils, and tiny particles settle between the burrs, in the chute, and inside crevices. Over time, these residues go rancid — the oils oxidize, just like coffee stored out in the open. Rancid residues mix with freshly ground coffee and impart a musty, bitter aftertaste.

The simplest and most important cleaning step: brush it out regularly. To do this, turn off the grinder (or remove the burrs on a hand grinder), empty the hopper, and use a dry, soft brush — ideally the grinder cleaning brush it came with — to clear out all residues. Check between the burrs, the exit chute, and the edges of the grinding chamber. Hand grinders can usually be completely disassembled, which makes cleaning much easier.

Cleaning pellets are made from food-safe ingredients. You pour a portion (20–30 g) into the hopper and grind it through. The pellets bind coffee oils and push out old residues from the system. Afterward, run a half handful of coffee beans through to clear out any pellet remnants. You can do this every 2–4 weeks — or whenever your coffee suddenly tastes off, even though you haven't changed the beans or grind setting.

No water. Burrs made of steel or ceramic do not tolerate moisture. Water leads to rust (with steel), clumping of coffee residues, and in the worst case, jammed burrs. If you want to thoroughly clean the grinding mechanism, use a dry cloth or compressed air.

A special case is grinders with an integrated portafilter fork (grind-on-demand): residues collect in the chute here, which should be regularly cleaned out with a dry brush. Stale coffee grounds in the chute are the most common reason for unexpected flavor changes.

In practice at Green Wall Coffee

At Sophienstraße 27, we usually clean the grinders every two weeks. When a guest tells me their coffee at home suddenly tastes weird, I always ask first: when did you last clean your grinder? Often, that alone solves it.

Feel free to drop by for a coffee — Green Wall Coffee, Sophienstraße 27 in Berlin-Lichtenberg, Mon–Fri 8am–5pm and Sat 10am–5pm.

Further reading

In-depth article: How to Make Perfect Espresso

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