It has the reputation of being THE entry-level grinder for the world of espresso. The Graef CM800 is often sold as an affordable entry-level machine, but just how good is it? What can you expect for 130 euros and is it really suitable for getting started? We put the Graef through its paces and were frustrated after the first few hours! The coffee just didn't taste right. But we didn't give up on it; instead, we continued to test and tinker until we could get something decent out of the machine. Our two-year journey with the Graef is summarized in this report.
Why do we test the way we do, and why do we test at all?
Our goal is to introduce you to machines and tips that will help you achieve a great coffee experience with simple means and a limited budget. That's why we, the Kaffeemacher:innen, operate our own coffee farm, a roastery and cafés, as well as a coffee academy.
When we recommend a machine, it's because we are convinced by it and know that you can make good coffee with it. If operating tips are necessary for a good result, we provide them along with it. For the sake of transparency: We earn nothing from this machine or our tips, which is why we can be completely honest from the start!
Overall impression of the Graef CM 800
The price and the size are the big plus points of the Graef. 13.5 cm deep, 23 cm wide, and 39 cm high allow it to fit into any kitchen. Its build quality feels solid at 2.6 kg.
Another plus point: It CAN produce espresso-fine coffee powder, unlike other grinders in the price range up to €200. So, if you find the right setting for your beans, you can actually brew a proper espresso.
Our verdict on the Graef CM 800 in advance
So, you can grind espresso-fine. But getting to the right grind size is extremely difficult. Operating the machine is not easy. You should even be able to handle a screwdriver to get everything you can out of the grinder. In our opinion, the Graef is suitable for sensory novices and those who are technically advanced.
Grinding espresso fresh with the Graef CM800
Coffee loses aroma extremely quickly just 15 minutes after grinding. This is due to the massive increase in surface area and the reaction of the powder with the oxygen in the air. That is why pre-ground coffee is always worse than freshly ground. Espresso grinders can grind finer than coffee grinders. This is necessary to build up appropriate resistance during espresso preparation. If the powder is ground too coarsely, the espresso flows through too quickly and the coffee is not sufficiently extracted (under-extraction), making it taste sour. The Graef can therefore make a big difference in taste, a quantum leap from pre-ground to freshly ground espresso.
Can something so cheap be delicious?
We spent many hours with the Graef mastering the complex grind adjustment and brewing a perfect espresso. To ensure our negative points weren't due to the espresso machine itself, we pulled the espressi using a La Marzocco GS3, which is in the price range of a small car.
Our espressi were bitter and simultaneously had an aggressive acidity. Despite our usual brew ratio (18 grams of coffee to 45 grams of espresso) and an optimal extraction time of 25 seconds, the espresso did not taste good.
To keep our subjective taste experience more objective, we used a so-called triangle test. In this test, three espressi are tasted blind. Two are from the same extraction, one differs. We also asked the tester to name the worst espresso. Out of 6 sets, the Graef CM 800 was always identified as the worst espresso.
Particle distribution as a reason for poor espresso
During the grinding process, coffee beans are ground into pieces of varying sizes. This results in some larger particles and some smaller ones. This is known as particle distribution. The greater the spread of these particles, the more difficult it is to pull a balanced espresso. During extraction, the large coffee particles are under-extracted, and the small ones are over-extracted. Instead of a balanced cup, this results in a mixture of bitter and sour components. With the Graef, the particle distribution is too wide. Using a laboratory sieve, we were able to determine that out of 50 grams of espresso powder, only 20 grams were ground to the perfect size. About 10 grams were too fine, and about 20 grams were too coarse.
Grind analysis via laser and image capture
With the help of Benjamin Schütz, roaster and coffee professional, and the company SympaTec, we were able to compare the grind of different grinders. I set the grinders for a perfect espresso (18 grams of powder to 50 grams of beverage in 25 seconds). We tested the following grinders:
Anfim Practica as a professional benchmark, Eureka Mignon Perfetto, Macap M2D, Sage Smart Grinder Pro, Sette 270wi, Graef CM800.
The Graef CM 800 showed the lowest peak. That is, the grind is significantly scattered and does not have a truly uniform grind size. The amount of coarse particles is also higher than in the other grinders tested.
Lowest strength and extraction evaluation for the Graef CM800
Furthermore, we tested the "strength" of the coffee, i.e., the amount of dissolved coffee particles in the espresso. The Graef lagged significantly behind the other grinders. There were only about 17.9% dissolved coffee particles in the cup. Other grinders achieved up to 21.5%. In terms of taste, this resulted in a rather watery-tasting espresso.
Grinder test 2022 - Graef CM800 under scrutiny again
The tests we conducted in 2022 also support the results above. A re-analysis in the lab again showed a very wide distribution of particles and a high coarse peak. It is simply difficult to grind a specific size of coffee particles precisely.
Operation and grind adjustment of the Graef CM800
Grind adjustment is the most important setting for a coffee grinder. This is where you adjust how coarse or fine the powder needs to be to achieve the perfect flow rate during extraction.
The Graef has a setting range of 0-40. Unfortunately, even on the finest setting, the espresso rushed through in just 12 seconds. It was therefore still too coarse. For this reason, instead of the external setting, we had to make an internal adjustment to the burrs.
To do this, the grinder had to be opened and two small screws on the upper burr loosened. Then a coarse adjustment could be made to get into the correct range for espresso grinding. It's best to watch this in our Kaffeemacher:innen video.
While this type of adjustment is possible, it is very, very cumbersome and actually a no-go. Beginners in particular, who are attracted to this affordable grinder, are really put to the test here. There is a risk that instead of an introduction to the world of espresso, it will deter them from its complexity.
Grinding is done via an on/off button. The amount of powder must be weighed manually, as there is no timer function.
You can find suitable grinder cleaning powder here.
Retention for coffee powder
By retention, we mean hidden places in the coffee grinder where old coffee powder remains. The larger the retention, the more "old" coffee grounds you get in your portafilter during a grind. The retention of the Graef is about 8 grams. That's quite a lot!
Conclusion on the Graef CM800 and who is this grinder suitable for?
The biggest pro is that the Graef is the only grinder in its price segment that manages to grind espresso-fine. However, precise adjustment is very cumbersome if readjustment of the burrs is necessary.
The particle distribution of the ground coffee is so wide that even with the correct setting, the ground coffee is extracted incorrectly. There are then too many under- or over-extracted coffee particles.
Many beginners use the Graef together with the Delonghi Dedica EC 685. With both machines, it is possible to brew an espresso affordably, but whether it hits the right taste remains questionable. For beginners especially, it is important that your equipment functions reliably to quickly recognize adjustment errors. Therefore, we would not really recommend the Graef. If you don't mind a lot of ground coffee and breaking a sweat over the settings, you can give the Graef a try.
This article is a short blog post. You can find the detailed blog article here on our Swiss site.
