It has the reputation of being THE entry-level grinder for the world of espresso. The Graef CM800 is often marketed as an inexpensive entry-level machine, but how good is it? What can you expect for 130 Euros and is it really suitable for beginners? We tested the Graef thoroughly and were frustrated after the first few hours! The coffee didn't taste good. But we didn't give up on it; instead, we continued to test and tinker until we got something out of the machine. Our two-year journey with the Graef is summarized in this report.
Why we test this way and why we test at all?
Our goal is to introduce you to machines and tips on how to achieve a great coffee experience with simple means and a limited budget. That's why we at Kaffeemacher:innen operate our own coffee farm, a roastery and cafes, as well as a coffee academy.
When we recommend a machine, it's because we are convinced of it and know that you can make good coffee with it. If operating tips are necessary for a good result, you'll receive them as well. For transparency: We earn nothing from this machine or from our tips, so we can be completely honest!
Overall impression Graef CM 800
The price and size are the Graef's big advantages. With a depth of 13.5 cm, a width of 23 cm, and a height of 39 cm, it fits into any kitchen. Its workmanship feels solid at 2.6 kg.
Another plus: it CAN produce espresso-fine coffee grounds, 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 conclusion in advance on the Graef CM 800
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 out of the grinder. In our opinion, the Graef is suitable for sensory beginners and technically advanced users.
Freshly grinding espresso with the Graef CM800
Just 15 minutes after grinding, coffee loses a significant amount of aroma. This is due to the large increase in surface area and the reaction of the powder with oxygen in the air. That's why pre-ground coffee is always inferior to freshly ground coffee. Espresso grinders can grind finer than coffee grinders. This is necessary to build up adequate resistance during espresso preparation. If the powder is ground too coarsely, the espresso runs too quickly and the coffee is not sufficiently extracted (underextraction), making it taste sour. So, the Graef can 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 to master the elaborate grind setting and brew a perfect espresso. To ensure that our negative points were not due to the espresso machine itself, we brewed the espressos with a La Marzocco GS3, which is in the price segment of a small car.
Our espressos 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 perceived taste experience more objective, we applied the so-called Triangle Test. In this test, three espressos are tasted blind. Two are from the same shot, one differs. We also asked the tester to identify the worst espresso. In 6 sets, the Graef CM 800 was consistently identified as the worst espresso.
Grind distribution as a reason for bad espresso
During the grinding process, coffee beans are ground into pieces of slightly different sizes. This results in some larger and some smaller particles. This is called particle distribution. The wider the spread of these particles, the more difficult it is to extract a balanced espresso. During extraction, the large coffee particles are under-extracted, and the small ones are over-extracted. This results in a mix of bitter and acidic components, instead of a balanced cup. With the Graef, the particle distribution is too wide. With 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. Approximately 10 grams were too fine, and about 20 grams were too coarse.
Grind size analysis using laser and image capture
With the help of Benjamin Schütz, roaster and coffee professional, and the company Symphatec, 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. This means that the grind scatters significantly 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 was significantly behind the other grinders. Only about 17.9% of dissolved coffee particles were found in the cup. Other grinders reached up to 21.5%. In terms of taste, this resulted in a rather watery-tasting espresso.
Grinder test 2022 - Graef CM800 under the microscope again
The tests we carried out in 2022 also confirm the above results. In a renewed laboratory analysis, a very broad distribution of particles and a high coarse peak were again observed. It is simply difficult to precisely grind a certain size of coffee particles.
Operation and grind setting of the Graef CM800
The grind setting is the most important adjustment option for the coffee grinder. Here you set how coarse or fine the powder needs to be to achieve the perfect flow rate during extraction.
On the Graef, there is an adjustment range from 0-40. Unfortunately, even on the finest setting, the espresso shot through in just 12 seconds. It was still too coarse. Therefore, instead of the external setting, we had to make an internal adjustment of the burrs.
For this, the grinder had to be opened and two small screws on the upper burr loosened. Then a rough adjustment could be made to get into the right range for grinding espresso. It's best to watch this in our Kaffeemacher:innen video.
This type of adjustment is possible, but it is very, very cumbersome and actually a no-go. Especially beginners, who are attracted by this inexpensive grinder, will be put to the test here. The danger exists that instead of an introduction to the world of espresso, it will rather be a deterrent to its complexity.
Grinding is done via an on and off button. The amount of powder must be weighed manually, as there is no timer function.
You can find suitable grinder cleaning powder here.
Dead space for coffee grounds
By dead space, we mean hidden places in the coffee grinder where old coffee grounds remain. The larger the dead space, the more "old" coffee grounds you will get in your portafilter when grinding. The dead space of the Graef is approx. 8 grams. That's quite a lot!
Conclusion on the Graef CM800 and for whom is this grinder suitable?
The biggest pro is that the Graef is the only grinder in its price segment that can 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 widely dispersed that the ground coffee is incorrectly extracted despite the correct setting. This results in too many under- or over-extracted coffee particles.
Many beginners use the Graef together with the Delonghi Dedica EC 685. Both machines allow you to brew an inexpensive espresso, but whether it will hit the mark taste-wise remains questionable. Especially for beginners, it is important that your equipment functions reliably in order to quickly identify setting errors. Therefore, we would not really recommend the Graef. If you don't shy away from a lot of ground coffee powder and sweating over the settings, you can try the Graef.
This article is a short blog. You can find the detailed blog article here on our Swiss site.
