How often should I replace grinder burrs?

Burrs wear. The cutting edges round off, so they crush more and cut less, producing more fines and a wider particle distribution.

Rough lifespans

• Steel burrs: around 250 to 500 kg of coffee, depending on quality and how much you grind at espresso fineness.
• Ceramic burrs: substantially longer, often quoted at double, since ceramic holds an edge better.
• Titanium-coated or nitrogen-hardened: longer again.

For perspective, a household using 500 g a week gets through 26 kg a year. At that rate a steel burr set lasts a decade or more, which is why most home grinders never need new burrs.

Cafes replace them annually.

How to tell they are dull

The change is gradual, which is what makes it easy to miss. Watch for:

• Shots slowing at the same setting. More fines means more resistance, so you find yourself grinding coarser over time to keep the same shot time.
• More fines and dust in the grounds.
• Muddier flavour. Less clarity, more general bitterness, harder to dial in.
• Grinding taking longer for the same dose.

Before you replace them, clean them

The symptoms of dull burrs and dirty burrs are almost identical. Coffee oils and compacted fines build up on the cutting edges and in the threads, which slows grinding and widens the distribution exactly as wear does.

Take the burrs out, brush them, and if there is a lot of buildup use grinder cleaning tablets. On many grinders this restores performance completely.

What to buy

Manufacturer burrs are the safe choice, and on grinders like Baratza they are cheap and documented. Aftermarket burr sets exist for popular grinders and can genuinely improve on the originals, though alignment becomes more critical.