Chronologically, the most antique coffee grinder is the mortar and pestle. The next step on the grinder's evolution ladder is the millstone; afterwards came the roller mill, and finally, the electric coffee grinder.
The use of home grinding
In the previous section we saw the use of home roasting. Useless to mention that home grinding is also a must if we long for that certain completion feeling that only a fresh, full-aroma cup of coffee can provide.
When coffee is ground, it starts releasing two major compounds that are known as flavor carriers: carbon dioxide (CO2) and lipids. CO2 is also the cream builder in the espresso, the minuscule particles enclosing gas and most of the coffee flavors. Simultaneously, another gas starts working over the quality of the coffee, corrosively and irretrievably. That is oxygen (O2). O2 ruins the quality of ground coffee continuously, as well as it affects the aliments or the metallic surfaces.
The answer to this problem is grinding the needed amount of coffee right before brewing it. And for that we need a home coffee grinder.
The grinding size
Adjusting the ground size is essential for the coffee you want to brew and the device you are using. In the table below you can learn the use of all-size grounds, from coarse to extremely fine.
| Grounds Size | Coffee Appliances |
|---|---|
| coarse | percolators |
| medium | plungers, syphons |
| fine | filter coffee makers |
| fairly fine | espresso pots and Krups |
| very fine | espresso machines, except Krups |
| extremely fine | Turkish* ibrik |
*The coffee ground for espresso machines is known as 'very fine'. However, there is one type of ground that is even finer, the Turkish type, obtained with a Turkish coffee grinder (also known as 'Turkish pepper mill'). The Turkish coffee mill is a manual coffee grinder, shape of a cylinder and an old fashion allure.
Types of Coffee Grinders
There are two major types of coffee grinders, the blade and the burr coffee grinder.
I. The blade coffee grinder consists of a sharp blade that spins within a barrel-shaped precinct. The blade grinders are the most accessible machines for grinding coffee. Their prices range around 20$. The longer the blade spins, the finer the ground.
However, the blade grinder has a major drawback: the ground coffee is uneven. The finer grounds tend to fly around and deposit on the precinct walls, while the bigger ones stay in the middle. A long grinding process also provides high temperatures, and there is the disadvantage of burning the coffee.
The blade grinder is commonly known as 'coffee mill' or 'spice mill'. It is not the best choice to grind coffee, but it's still much better than using stale ground coffee. Our advice, in case you spent all your money for the ultimate espresso machine, would be: 'buy a coffee mill for the moment, and start saving for a real grinder'.
II. The burr coffee grinder includes two versions: the flat wheel and conical burr.
- The flat wheel coffee grinder features a flat open hole disk placed over another metallic part. The coffee beens fall through the hole, between the two metallic wheels and are crushed. The burrs feature a knob for adjusting grounds size. What we do in fact when rotating the knob is modifying the distance between the two metal parts. The smaller the distance, the finer the grounds.
The advantage of a burr grinder is that it produces an even ground, and less heat in the grinding chamber, preventing the coffee from being burned.
Apart from the shape of the upper metallic part, the burr coffee makers can also be classified as high speed and low speed.
- in the case of high speed burr grinders, the rotating wheel is directly connected to a small electric motor; the disadvantage of small motors is that they have to turn at high speeds in order to develop sufficient power, and to grind without bogging down. The high speed of the grinding process tends to charge the coffee with static electricity. In order to prevent this unpleasant effect, you need to soak a few beans (not all the charge) in water, before starting the grinding.
- low speed burr grinders are usually preferred over the high speed ones, as they produce less heat in the grinding chamber, less static electricity, are more solid and live longer. The hand crank coffee grinder, because it's manualy actioned, can be considered a low speed burr grinder. The most famous hand crank brands are Bisetti (Italy) and the Zassenhaus coffee grinder (Germany). The electric low speed burr grinders further classify into gear reduction burr grinders and direct drive burr grinders.
- The gear reduction grinder is in fact a high speed burr grinder, but its motor is connected to a gear reduction system; the motion of the metallic wheel becomes slower but more powerful.
- The direct drive grinders have a big motor that is connected directly to the spinning wheel; these grinders are among the most expensive, but also the best coffee grinders available. See how burr grinder brands classify in the table below.
| High Speed Grinders | Gear Reduction Grinders | Direct Drive Grinders |
|---|---|---|
| La Pavoni coffee grinder, model PA | Bodum coffee grinder, model Antigua | Rancilio Rocky burr grinder |
| Capresso coffee grinder, model #551 | Solis Maestro coffee grinder | Rancilio MD 40 burr grinder |
| Capresso coffee grinder, model Select #555 | Solis Maestro Plus coffee grinder | Mazzer Mini burr grinder |
| Saeco coffee grinder, model MC2002 | Gaggia Coffee Grinder, model MDF | Pasquini Moka burr grinder |
If you want to buy a cheap coffee grinder, you can settle for Braun, Capresso, Bunn, Bodum, DeLonghi, Krups, Kitchenaid, Cuisinart; prices range from $20 to $60.
As for the high-end price category ($150 and more), we can mention the Rancilio Rocky Grinder, Solis Maestro and Solis Maestro Plus, Mazzer Mini, Pasquini Moka, Innova Grinders, Gaggia MDF, Nuova Simonelli MCF.
Commercial Coffee Grinders
Usually, a commercial coffee grinder is the conical burr type and is not available for less than $300. Some of the most 'affordable' commercial grinders are La Pavoni 'Jolly' model and Gaggia MDF Macinadosatore. There are, of course, home use grinders that use a conical burr, but they usually come in a plastic burr carrier, that can easily break.