How to Clean a Coffee Grinder with Cleaning Tablets

If you’ve used a grinder for more than a few weeks, you’ve probably noticed it: a faint stale smell, oils lingering in the chute, and flavors that just don’t pop like they used to. Even after brushing and scraping, some gunk remains deep in the burrs and grinding chamber. That’s where cleaning tablets come in—but do they actually work?

Yes, but only if you use enough. In our test, 25 URNEX GRINDZ tablets barely made a dent, but 50 fully cleaned the burrs of a flat-burr grinder, removing oily residue and eliminating stale odors—without taking the machine apart.

What Are Coffee Grinder Cleaning Tablets?

URNEX GRINDZ tablets were developed in partnership with German grinder manufacturer Mahlkönig. They’re made primarily from corn, are food-safe, and designed to mimic coffee beans in size and density—so they grind like real coffee, but scrub your burrs and clear built-up oils and coffee dust from inside the grinder.

Why Residual Coffee Oils Are a Problem

Over time, ground coffee leaves behind oils that coat the burrs and accumulate in the grinding chamber and chute. These oils oxidize, leading to off-flavors and a rancid smell. Even regular brushing can’t fully remove material stuck in tight spaces. That’s why chemical or food-safe cleaning tablets are useful—they reach where brushes can’t.

Our Cleaning Test: What Worked and What Didn’t

We started with a standard home grinder fitted with flat burrs (not specified, but larger than conical sizes like those on a Baratza Encore or similar). Before cleaning, we inspected the burrs and grinding path—the usual buildup of dark, oily residue was visible, especially on the burr edges and in the chute.

Following the instructions, we first tried just 25 GRINDZ tablets (we were trying to conserve them, since they’re pricey). We set the grinder to its finest setting to keep the tablets in contact with the burrs longer. After grinding, we opened the burr chamber and saw minor improvement on the burr surface, but the grinding path and chute were still packed with old coffee dust. Conclusion: 25 tablets weren’t enough for a full-size flat-burr grinder.

So we added another 25 tablets—50 total—and ran them again at the finest grind setting. This time, the difference was obvious: the burrs looked shiny and clean, almost like new, with no visible oil residue. A quick pass with a clean brush removed the last bits of debris, and the grinding path showed noticeable improvement, though some dust remained in harder-to-reach areas. The smell was completely gone.

The entire process took less than 10 minutes, no disassembly required.

Does It Affect the Taste of Your Next Coffee?

We followed up with a batch of freshly ground Geisha (Yirgacheffe) beans to check for any lingering taste from the tablets. Result? No odd flavors, no corn taste—just clean, fresh coffee. No detectable aftertaste from the cleaning process.

Which Grinders Benefit Most?

GRINDZ tablets are ideal for grinders that are hard to disassemble, such as built-in grinders on super-automatic machines or certain semi-automatics. They also work well for smaller conical burr grinders, where tablets stay in the burr path longer due to slower RPMs. Flat burrs, especially large ones like those on a Mazzer Major, require more tablets and may not be as cost-effective. But for most home users, occasional cleaning with GRINDZ is a practical solution.

Frequently Asked Questions

How many GRINDZ tablets should I use per cleaning?

For a standard home grinder with flat burrs, 50 tablets gave the best results in our test. Fewer (like 25) only lightly cleaned the burrs but left the grinding channel dirty. Adjust based on your grinder size.

Do I need to disassemble my grinder to use GRINDZ?

No. One of the main benefits is that GRINDZ cleans without taking apart the burr set or grinding chamber. Just run the tablets like regular coffee, then brush out any remaining dust.

What’s the best grind setting to use with GRINDZ?

Set your grinder to its finest setting. This keeps the tablets in the burr chamber longer, improving contact time and cleaning effectiveness.

Will GRINDZ leave a weird taste in my next coffee?

Not if you dose and clean properly. Our test showed no residual taste after grinding fresh Geisha beans immediately following the cleaning process.

Are GRINDZ safe to use?

Yes. They’re made primarily from corn and are non-toxic and food-safe. They’re also certified and tested in partnership with Mahlkönig, a leading grinder manufacturer.

Recommended FrontStreet Beans for Grinder Maintenance

To test your freshly cleaned grinder, try FrontStreet Coffee’s Ethiopia Humbera (Geisha), known for its jasmine tea and lemon zest brightness, or the Yirgacheffe, which highlights citrus and floral notes—both ideal for spotting grinder flaws. For a richer profile, the PWN Golden Mandheling offers heavy body and sweet spice, excellent for checking mid-range grind performance. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.