There are many types of coffee grinder available on the market, with a wide variety of applications and technologies in use. These different types of grinder offer a diverse range of coffee grinding mechanisms, and the mechanisms through which each operate differ in their quality of grind and the maintenance requirement required.
The simplest coffee grinder is the traditional and primitive stone mortar and pestle system, still employed in many parts of the world where coffee is consumed. Roast beans are placed in the well of the mortar and ground to the desired fineness by the action of the pestle. This is a time consuming and labor intensive process, requiring several minutes of grinding to reach a fine powder state. In a commercial environment this approach should only be used if there is no other grinding equipment available.
The use of a hand powered mincer can increase the speed of the grinding process, but the quality of the grind is very coarse, and still requires manual operation. Again, only if there is not a more suitable option for grinding should the hand mincer be used.
A more common type of grinder is the blade grinder. This is a simple device with an electronic or mechanically driven blade, that whirls around in a cavity at a rapid rate, finely chopping the roast coffee beans to a fineness controlled by the length of time that the machine operates. These can provide a very fine grind, but often do not provide the uniform quality of grind required for the operation of a commercial espresso machine. Suited for the small scale coffee drinker with an appreciation of fresh ground coffee, the blade grinder is a very useful addition to the kitchen.
Care should be taken with blade grinders to avoid operation when the lid is off, as the rapidly rotating blade can endanger the fingers and other fleshy extremities. Always ensure the machine is switched off when loading, and if it begins to malfunction it may be time to find another.
If the small blade grinder does stop working, all is not lost, often they can be fixed. If it is just a matter of coffee grinds blocking the mechanism that controls the on off switch, or a screw becoming loose through continued vibration, then five minutes of careful attention with the correct tool will allow you to restore the grinder to operation. If it cannot be fixed easily, then a kitchen blender will also work to grind coffee beans to a fine powder, though the larger size of the cavity makes it more difficult to remove the ground coffee once a desired texture has been reached. Make sure the lid is on otherwise there will be coffee beans everywhere in the kitchen.
More sophisticated technologies do exist. The most ideal coffee grinder for most applications is the Burr Grinder. This is a device with rotating grinding teeth, set up in an arrangement to allow the distance between the teeth to be adjusted, and the particle size of the ground coffee to be increased or reduced as demand requires. Often found in a cafe, these grinders can grind coffee as fast as beans can fall through the rapidly whirring teeth. Being more resilient and sturdy in their construction, these grinders often carry a much higher price tag than a blade grinder. Careful hunting at a thrift sales and auctions can often result in picking up a commercial quality burr grinder for a low price.
Take care though, make sure that you are only grinding coffee in the grinder otherwise the teeth may clog and cease operating properly. Clean the mechanism regularly, in order to maintain functionality of your grinder and great tasting coffee. A top quality burr grinder will last several years of rigorous daily use if it is looked after properly.
