How to Clean Your Grinder Burrs with Cleaning Tablets

If your grinder has been sitting for a while—or even if you clean it regularly—you’ve probably noticed a lingering coffee smell or a faint oily residue inside. No matter how thoroughly you brush and scrape, some coffee oils and fine particles just stick around, affecting taste and performance. That’s where cleaning tablets come in.

The short answer: 25 tablets may be enough for a light clean, but for best results—clearing both burrs and grinding chamber—use closer to 50 tablets of Urnex Grindz, set your grinder to its finest setting, and run them through like coffee. This removes built-up oils and odours effectively.

What Are Grinder Cleaning Tablets?

Urnex Grindz are cleaning tablets co-developed and tested with German grinder manufacturer Mahlkönig. They’re made primarily from corn, are non-toxic, and completely food-safe—approved under both U.S. and German food regulations. Their purpose? To clear out old coffee oils, flavours, and trapped particles from your grinder’s burrs and grinding path without disassembly.

Why Residue Builds Up in Your Grinder

Over time, coffee oils and fine coffee dust accumulate inside your grinder, especially on the burrs and in the grinding channel. Even with regular brushing, oils cling to metal surfaces, harden, and trap odours and stale flavours. This buildup can subtly alter the taste of freshly ground coffee, especially if you switch between beans frequently.

Traditional cleaning methods involve taking apart the burr set, brushing, and scraping—but that’s time-consuming and doesn’t always reach the grinding channel or remove all the oil film.

How We Tested Urnex Grindz on a Flat Burr Grinder

In this trial, a flat burr grinder (not specified as Mahlkönig or Mazzer but implied to be of similar commercial grade) was used. The user began with a visual inspection

, noting visible residue even after standard cleaning. They then loaded approximately 25 Grindz tablets—described as “a bit expensive, so they went light”—and ran them through the grinder at its finest grind setting

.

The user initially thought the effect was minimal, noticing brightness on the burrs but persistent residue in the grinding channel. On the second attempt, they used a similar amount (roughly 25 more tablets), kept the grind setting at finest, and saw clearer results: burrs appeared shiny and clean, free of oil residue. The grinding channel still had some leftover coffee dust, but the internal oils were mostly gone [[IMG3], [IMG4], [IMG5]].

They noted that the cleaning worked best when the tablets were allowed to dwell in the burrs longer—which happens more easily with smaller burrs or slower RPM grinders like conical models. Flat burrs, especially larger ones (such as those on a Mazzer Major), may require more tablets or more frequent cleaning due to higher throughput and faster grinding speeds.

Does It Affect the Taste of Your Next Coffee?

After cleaning, the user ground five Geisha (Ethiopia Yirgacheffe) beans and made a cup, adding two more scoops for a proper brew. Despite concerns about residual corn flavour, none was detected in the cup. The cleaning tablets did their job without leaving any off-notes.

Best Use Cases for Grindz Cleaning Tablets

These tablets are especially useful for:

• Super-automatic espresso machines with built-in, non-removable grinders
• Home espresso grinders where burr removal is difficult
• Grinders with conical burrs, which grind more slowly and let the tablets dwell longer
• Any grinder used daily where regular deep cleaning is impractical

They’re less cost-effective for very large flat burr grinders (like the Mazzer Major), but still usable—just plan on using more tablets per session. One bottle of Grindz lasts a long time if used occasionally, as deep cleaning doesn’t need to be done after every bag.

Frequently Asked Questions

How many Urnex Grindz tablets should I use per clean?

For a thorough clean, use around 50 tablets. The tester initially used 25 tablets and saw partial results, but achieved a fuller clean (including the burrs and most of the grinding channel) with roughly 50 tablets. Fewer may work for light maintenance or smaller grinders.

Do I need to disassemble my grinder to use Grindz?

No. Grindz are designed to be used without taking apart the grinder. Simply run the tablets through like coffee, using a fine grind setting, and let them clean the burrs and grinding path internally.

Will Grindz leave a corn flavour in my coffee?

Not if used properly. The tester reported no corn taste after cleaning and brewing Geisha beans immediately afterward. The tablets are made from food-safe corn but are formulated not to transfer flavours when used as directed.

Are Grindz suitable for conical burr grinders?

Yes, and they may work even better with conical burrs. Since conical burrs often turn more slowly than flat burrs, the cleaning tablets have more contact time with the burrs, improving effectiveness—especially in lower-RPM home grinders.

How often should I clean my grinder with Grindz?

It depends on use, but for daily or near-daily use, once a month is a good rule of thumb. If you switch coffee beans frequently or notice flavour carryover, clean more often. For occasional use, every couple of months may suffice.

Recommended FrontStreet Coffee for Grinder Maintenance

To test your freshly cleaned grinder, try FrontStreet Coffee’s Ethiopia Yirgacheffe—bright, floral, and aromatic, perfect for spotting channeling or residue issues. Also consider their Panama Geisha Humbera, known for its juicy sweetness and tea-like body, which highlights subtle grinder performance. For something more everyday, their Classic Blend offers balanced body and chocolatey notes, ideal for routine espresso. All beans are freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.