Here is an FAQ written by the manufacturer (Urnex) about Grindz ... some useful information here...  

Grindz Grinder Cleaner Frequently Asked Questions

What is Grindz Grinder Cleaner?

The product is the first ever cleaner for coffee grinders. What is Grindz Grind Cleaner made of, and what does it look like? The product is a proprietary formula of grains, cereals, and pharmaceutical grade binders in a coffee bean shaped tablet. 

Who developed Grindz Grinder Cleaner?

The product was developed by the technical team at Urnex Brands, Inc. It was inspired by a meeting between the owners of Urnex and Mahlkoenig when the challenges of grinder care and cleaning were discussed.

Why was Grindz Grinder Cleaner developed?

In pursuit of ways to help customers serve the best tasting coffee, we have dedicated itself to helping eliminate the chance of coffee oil residue contaminating future brews.  Cleaning a grinder has always been a challenge since water cannot be used on the burrs or around electric motors.  The process of opening a grinder can also be very intimidating due to the small parts and precision involved in positioning burrs.  Finding a way to clean a grinder without opening the machine became a valuable product concept.

How does Grindz Grinder Cleaner work?

When ground through your coffee grinder, the product gently dislodges coffee particles while also absorbing coffee oil residue. 

Is Grindz Grinder Cleaner a chemical?

No. There are only food safe and edible ingredients in this product.  As a result, the product presents no risk if the residue is consumed, and it will be flavor neutral to your coffee.

How was Grindz Grinder Cleaner tested?

Throughout the development process, the team at Urnex worked very closely with the technical staff at Mahlkoenig in Hamburg, Germany.  Every version was evaluated for safety and effectiveness on a broad range of grinders.

How do I use Grindz Grinder Cleaner?

Simply take the recommended dose (40g for espresso grinders and 80g for shop grinders) and drop it into an empty grinder hopper.  You can also use the cap of the jar for dosing. A full cap will yield between 33-40 grams.  Adjust machine setting to medium, and operate as if grinding coffee beans.  Once complete, we recommend passing twice as much coffee through to purge any residue.

What happens if I use a setting other than medium with Grindz Grinder Cleaner?

This is not a problem at all. In fact, you may want to experiment with Grindz Grinder Cleaner and different settings on your machine.  We found that medium setting delivered the optimal cleaning effect. However, this may vary with your equipment and the amount of coffee residue.

Will Grindz Grinder Cleaner remove flavored coffee oil?

Yes. We have found the product to be effective at eliminating the scent of flavored coffee. It is particularly effective in removing the odor of flavored coffee when it has accidentally been passed through the dedicated "non-flavored" grinder.

Why should I use Grindz Grinder Cleaner regularly?

Just as any coffee machine should be cleaned regularly, a grinder should be cleaned in the same manner to achieve the optimum grinding quality. Grindz is an easy way to remove the coffee residue and oils deposited on grinder burrs. The regular use of Grindz lengthens the time period between one servicing and the next, and also reduces the need to disassemble the grinder to clean it. Thus, making maintenance less costly, more timely and efficient.

How often should I use Grindz Grinder Cleaner?

It is recommended to use Grindz for espresso grinders once a week and for shop-grinders once a month.

Why can't I just use rice to clean my grinder?

In the past, many people have cleaned grinders with rice.  However, rice carries the risk of locking up the motor of a grinder as it passes through and is turned into a fine powder.  The hardness and shape of Grindz Grinder Cleaner prevents this from happening.  Using rice to clean your grinder also leaves a starchy residue on the inner mechanics of a grinder that is difficult to remove.

When I use Grindz Grinder Cleaner, I am left with a lot of white dusty particles in my doser.  How do I get this out?

The dust created by using Grindz Grinder Cleaner is harmless and flavor neutral.  However, it should be passed through your doser and brushed out. If you have trouble getting it all out, we recommend using a vacuum to clean out the tiny areas.

How should Grindz Grinder Cleaner be stored?

It is best to keep in a cool dry place with the lid on.  Each jar is marked with a "best before" date to suggest use within one year of production.

Green Coffee Beans 70+ Selections Hearthware I-Roast 2 Fresh Roast Home Coffee Roasters - Two Models Gene Caffe Drum Roaster
Behmor 1600 HotTop Drum Roaster Stovetop Popper Roasting Espresso Equipment & Accessories
Nesco Home Coffee Roaster Technivorm Electric Brewers Chemex Coffee Brewers Coffee Bags: for green and roasted
Zassenhaus Hand-Crank Mills Nissan & Zojirushi Travel Cups/ Bottles Vacuum Brewers: Cona, Yama Coffee Cleaning Supplies
Espresso Machines: Giotto Professional and Premium, Rancilio Silvia, Andreja Premium , Gaggia, Coffee Books
Miscellany and Sweet Maria's T-Shirts
Electric Coffee Mills: Mazzer Mini, Maestro, Rancilio Rocky, Bodum Manual Drip Brewing
Our Roasted Coffee French Press Coffee Brewing Ibrik: Turkish Coffee Brewing Mokapot: Stovetop Espresso