What are the differences between coffee grinders? And which grinder best suits your needs? We explain to you what to look for in a good coffee grinder and what special features there are.
Why should you grind coffee freshly?
Nothing beats freshly ground coffee. And that smell of freshly ground coffee from the grinder is worth getting out of bed for. This beautiful smell, however, also has its sad drawback: all the aromas you smell are soon gone and gone forever, never to find a home in your cup of coffee. In the truest sense of the word, they’ve dissolved.
Drafts, light, and heat are aroma killers
Through the process of cracking open those beans through grinding, the bean cells open and carbon dioxide (CO2), aromas, coffee oils and other ingredients escape. These substances further dissolve during the subsequent brewing. Since many of the fine aromas react with oxygen, light and heat, the coffee should be ground only shortly before the preparation. Ergo: coffee is a fresh product and should be served fresh to maintain the optimum range of flavors in every cup of coffee.
How do you recognize a good coffee grinder?
- The mill crushes the coffee beans without heating them. In other words, the motor and grinder do not produce too much heat. If the beans are heated too much during grinding, the coffee oils change and the coffee tastes bitter or burnt.
- The mill produces evenly cut coffee grinds. Since every coffee bean is different by nature, no coffee grinder can succeed in grinding the beans in an identical size. However, it is possible to get a nice homogeneous grind resulting in a more uniform extraction of the good stuff.
What kind of grinders are in each grinding machine?
Mills with percussion blades
These models were often used in the 1980s and 1990s. The coffee beans are ground by rotating blades. The problem is that the coffee is very unevenly ground, which results in uneven extraction. Moreover, the coffee is heated too much during the grinding. This impacts the coffee oils and the resulting coffee drink tastes bitter and unpleasantly intense. Therefore, we advise against these grinders. Current models can be found in our large coffee grinder test.
On these two photos you can see very well why we generally advise against the purchase of percussion grinders: The grist contains both half beans and small particles. A more uneven result could hardly be possible!
Electric Grinders with burr grinder
Mills with burr grinders are currently most commonly used. The beans are ground in a concave form between two successive grinding discs. One of the two disks is driven by a motor and the other disk is fixed. The distance between the two discs is slightly larger on the inside than on the outside. The bean reaches from the inside between the disks, is broken up and then transported further outwards by the centrifugal force. Since the grinding disks lie closer together on the outside, the bean is always ground finer. The distance between the discs is changed to adjust the degree of grinding. The grinding disks are usually made of steel or ceramic. Good grinders have a very long life.
Electric grinders with conical mill
In grinders with a conical grinding mill, the coffee beans are crushed between the inner cone and the outer wall. The distance between the cone and the wall becomes smaller and smaller so that the beans are always finely ground. The degree of grinding can be varied by means of the distance between the cone and the wall. In contrast to a disk grinding mill, the output is not carried sideways. Rather it falls downwards and into a collecting container. For this reason, the speed of a conical grinding mill is lower and the ground coffee is very aromatic.
Hand grinders represent a good and inexpensive alternative to electric grinders for using at home. They have a conical grinding mill, in which the degree of grinding can be adjusted. All in all, the Hario hand grinders impress with their evenly sized output. Due to the compact size, hand mills can also be easily transported – and make fantastic travel companions.
Buy your coffee as a whole bean and not pre-ground. We can highly recommend electric grinders with disk and conical grinders as well as hand mills. With a grinder you are also more independent of preset grinding degrees and you can fine-tune your grind depending on the preparation method and personal taste.