Burr seasoning

The process of running 5–20 kg of coffee through new burrs to smooth out micro-roughness on the cutting edges. New burrs often shed tiny metal slivers and feel "rough" before they bed in.

Why it matters — Brand-new burrs often produce inconsistent, unusually bright shots for their first few kilos of coffee. Seasoning brings them to the smoother, more stable behaviour they'll have for the rest of their life.

Good to know

• Don't expect perfect espresso on day one with a new grinder. Stale beans for seasoning are fine — you're not drinking the output.
• Some modern burrs (especially diamond-coated or harder steels) season faster (1–3 kg) than older types.