Whether you're buying pre-ground coffee or grinding it yourself from whole beans, the texture of the grind should be correlated to the method of brewing. The coarsest grinds are used for open-pot brewing and percolators. A slightly finer, but still coarse grind is used for the French press, since the particles have to be large enough to be corralled by the filter. Automatic drip brewers can use a finer grind, since the paper filters capture any sediment. The finest grinds are used for espresso and Turkish coffee.

Generally speaking, you should use the finest-ground coffee that will work for your method of brewing. The finer the grind, the more flavor elements are exposed to the hot water. Don't pulverize it completely into powder, though, or the heat of the grinding process will destroy some of those flavor elements. Coffee ground too finely may also clog your machine and produce a muddy brew.

Ground Coffee at Home

To get the freshest cup of coffee, grind only those beans you will use right away. There are two basic types of home grinders, burr grinders and blade grinders. Burr grinders feed the beans one or two at a time between two corrugated metal plates. One stays stationary while the other moves. Burr grinders produce very consistently ground coffee, since the grind is calibrated by the distance between the plates.

Blade grinders are like miniature blenders. Two blades rotate at high speed and basically knock the beans into pieces. The fineness of the grind depends entirely on how long the blades are spun. For finer grinds, it is best to do it in bursts. Both types of grinders should be cleaned regularly, and burr grinders should never be used for flavored coffees, since the additives stick to the plates.