Coffee Grinder
Picking The Perfect Coffee
Grinder
Coffee beans, like any food product,
oxidize when exposed to air. The grounds, since they have a
much larger relative surface area than the bean, and no
covering, suffer this effect even more. Grinding beans at home
produces the least exposure to air and the freshest grounds.
And you can grind only what you immediately need. In the old
days a manual coffee grinder (coffee grinders
were little boxes with a manual grinder in the middle)were
normally used for this purpose.
But nothing is without its price. Grinding is time consuming
and messy, so if you choose to invest the effort to reap the
reward, pick the best coffee grinder you can afford.
Coffee Grinders fall into three
broad categories - burr, blade and
crusher.
The third type is some kind of mashing device, often an
ancient-style mortar and pestle. These crush the beans, which
is difficult and produces a very uneven sized granule. Not
recommended where you have a choice.
The blade grinders don't actually grind at
all, they chop. A whirling blade slices the beans into smaller
and smaller sections until they approach something like a small
grain. Unfortunately, the grains are invariably too large and
of inconsistent size.
As a consequence the surface areas of the granules vary,
releasing varying amounts of flavor oils when brewed. Another
effect of slicing is often the production of excess heat, as a
result of the high speed of the blades. That friction warms the
grounds and partially dissipates the aroma.
The first type is the first choice. Burr
grinders have a pair of motor driven plates with
pyramid-shaped teeth that grind the beans to a consistent,
small-but-not-too-small granule. The better models allow
adjusting the size of the grain and the speed of the
grinding.
Adjusting the size is important in order to 'fine tune' the
grounds to allow just the desired brew. Controlling the speed
keeps the warming effect to a minimum.
Even burr grinders fall into two classes - the conical burr
grinder is preferred by real coffee aficionados. Though
noisier, they allow the most control of grain size and
speed.
Good conical burr grinders can rotate as slowly as 500rpm.
By contrast other burr grinders spin at 10,000rpm or higher,
blades between 20-30,000rpm. That allows very fine control and
little heat. The fine grind is especially important for
Turkish-style brews. Some grinders have a continuous dial,
others have a series of up to 40 steps to adjust the granule
size.
Beyond those broad attributes, the home barista will want to
look for solid construction, ease of cleaning and low noise. A
cleaning brush and removable upper burrs is essential.
Different materials used can also affect how much static
electricity is produced - that causes the grains to stick to
the burrs and container.
A timer switch and auto-shutoff is a nice addition and being
able to see the beans as well as the grounds is helpful for
judging the results in the grinder. Dark plastic or glass may
be aesthetically appealing but it obscures the view. Grounds
can change color slightly depending on the fineness.
Read reviews and be prepared to spend a little more and
you'll be rewarded with the freshest, most flavorful cup.
Bon cafetite!
|