|4 Storing, Grinding, and Cleaning Up|
|4.1 How to store coffee|
|4.2 Coffee grinders|
|4.2.1 Burr grinders versus blade grinders|
|4.2.2 Flat Plate Burr Grinders vs. Conical Burr Grinders|
|4.2.3 Manual Grinders|
|4.3 Cleaning coffee makers|
|4.3.2 Removing coffee deposits stains|
4.1 How to store coffee
This is a common question in online discussions about coffee, and it never fails to cause dissension.
Coffee beans must be isolated from air and moisture. Probably the best storage
containers are made from glass or glazed ceramic, which have the added benefit
of being easily cleaned. If glass is used, the container should be kept in a
dark location (if only because light is, theoretically, usually an accelerant
to chemical processes); in either case, the containers must be able to maintain
an air- and moisture-proof seal. Alternately, mylar/plastic bags with one-way
valves can also do a fine job so long as care is taken to ensuring an airtight
seal. Regardless of the container, as stated above, do not purchase more whole-bean
coffee than can be consumed in approximately a week to two weeks post-roast.
Beans primarily stale as a result of the loss of aromatic and volatile compounds,
which occurs continually with the outgassing of carbon dioxide (see "Degassing,
resting, and storage" in the section on home coffee roasting).
The effects of freezing are disputed. Some feel that the freezing will damage the subtle tastes in the coffee; less disputed is that moisture will condense on the cold beans each time the container is opened. At the least, avoid repeatedly opening the freezer-stored coffee: divide up your coffee supply into multiple containers (with as little airspace as possible) and keep one container out for use, not replacing it in the freezer after it is opened. If you do not have a local roaster, you may do well by ordering three or four pounds at a time from a mail-order roaster, dividing the order into half-pound batches, and freezing them all. Take out a pack as you need it, allow it to return to room temperature before opening, and do not refreeze.
Do not store coffee in the refrigerators; they are moist, smelly places.
4.2 Coffee grinders
Grinding your own coffee is one of the best steps you can take towards a superior brew. Coffee stales quickly after it is ground; buying fresh coffee from a local roaster and having them grind it in the store largely negates the benefits of purchasing recently roasted coffee.
The most commonly found grinders look like miniature blenders, and they operate by chopping up the beans with two or more sharp blades spinning at high speeds. Less common are burr grinders: the beans are placed in a hopper on top of the machine, and they feed between two metal rings (burrs) and down into a bin. One of the burrs is fixed in place and the other rotates a small distance away from it; the beans are fed into a hole in the center of the top burr and are sliced down by the burr teeth as they make their way between the two burrs to the outside, where they are ejected. Manually operated versions can be purchased, as well as the electric models. The hand-cranked models are related to flour mills, but home flour mills will not usually grind coffee well and may become clogged by the coffee oils.
4.2.1 Burr grinders versus blade grinders
Blade grinders (also called "whirly blade" grinders) are not able to produce a consistent particle size: the size of the grounds in any particular batch will be quite varied. As a result, coffee extraction will be uneven, with the larger particles underextracting (producing thin, weak coffee), and the smaller particles overextracting (producing bitter coffee); this does not "even out." This problem is undesirable for brewed coffee and a fatal flaw when making espresso. Part of the problem is that the user cannot control exactly what is being ground: one bean or bean piece may be chopped into smaller and smaller pieces, while another somewhat escapes the blades. This issue may be somewhat addressed by gently shaking the grinder while it is operating. Although certainly better than using stale coffee, blade grinders are best used for spices, though they may also work acceptably for producing the talcum-powder fine grind necessary for Turkish coffee.
4.2.2 Flat Plate Burr Grinders vs. Conical
There are two kinds of burr grinder:
1) flat-plate, shaped like two stacked dinner plates
2) conical, like two glasses stacked one inside the other.
For either type, each facing surfaces bears cutting teeth. As compared to a flat surface, a conical surface will have a greater grinding surface for a given diameter; imagine the cutting surface of a conical grinder being the hypotenuse of a right triangle, angling downwards, while the cutting surface of a flat grinder is the horizontal axis of the same triangle. The greater the angle away from the horizontal, the longer the hypotenuse (the conical burr) as compared to the side at zero degrees horizontal (the flat burr), even though the hypotenuse takes up the same horizontal distance. As a result, the conical grinders require a lower rotational speed, since the beans will feed through a longer distance with more burr contact.
That said, no conclusive results have come out of the arguments comparing the two types. However, some conclusions can be made. As always, price tends to go hand in hand with quality. The cheapest burr grinders—less than $50—are often little better than blade grinders. Their burrs are of lesser quality, and are often mounted in plastic carriers that do not hold the burrs rigidly, decreasing grind quality and burr life. The design and quality deficiencies of these inexpensive burr grinders do not justify their cost.
When researching brands, also look into how noisy each model is; some are surprisingly quiet, some sound like outdoor gardening tools. Some machines are prone to static problems, which can cause the grounds to fly all over the place, especially when humidity levels are low. Some machines have relatively long chutes between the burr chamber and the grounds bin; these long chutes may be prone to clogging. Some machines come with dosing chambers, which are meant to make it easier to fill an espresso machine portafilter. Some people like these chambers, others hate them, but they are of little use if you are not grinding for an espresso machine.
Some grinders use a worm gear to change grind fineness, for others, you rotate the top of the machine (usually, the bean hopper), effectively screwing the burrs closer together or further away. The worm gear is usually far more adjustable, but it is more difficult to repeatedly change back and forth between specific settings.
4.2.3 Manual Grinders
These are essentially burr grinders without the electric motors. Some of the better quality manual grinders (many people favor the Zassenhaus) produce excellent quality grinds. The downside is effort; it takes a significant amount of grinding to produce enough for a pot of coffee. The grinding time required to produce a particular quantity increases with the fineness of the grind, and the effort needed can be exasperating for espresso drinkers.
4.3 Cleaning coffee makers
Carafes should be well-rinsed after each brewing session. This includes autodrip, French press, thermal, or any other such devices that can be safely submerged and are used to hold brewed coffee—that is, you want to wash away the remains of the brew. Be mindful if you use an autodrip machine's warming plate, as it will often bake coffee residue onto the carafe bottom; the warming plate itself should be wiped off, when cool, with a slightly damp but not wet paper towel.Certain carafes contain integrated heating devices (e.g., the Bodum electric Santos vac pots and the ChefsChoice electric French press). These should have their insides well rinsed, but cannot be submerged.
Complete cleaning of coffee equipment requires separate acid and alkaline solutions. Acids (vinegar, citric acid) are necessary for cleaning mineral deposits, while a base (baking soda, most detergents) helps clean the weakly acidic coffee deposits.
Common sense dictates that you not immerse electrical equipment. As touched upon above, "cordless" electric carafes only contain part of their circuity inside their base. The rest is in the bottom of the water chamber, which therefore cannot be immersed, nor should its outside be allowed to get wet.
Note that special care is needed for espresso machines; see the particular machine's manual for this information.
Most auto-drip coffee makers require periodic descaling with a solution of water and vinegar. The brew water contains dissolved minerals that will come out of solution and coat the heating elements and other parts of the machine. If allowed to build up, this coating will impair the efficiency of the heating element. Vinegar will dissolve these minerals; cleaning solutions or powders are often sold for this purpose, but they are often little more than citric acid or a similar weak food-grade acid; their main advantage is that they don't have vinegar's strong odor or taste, so you are less likely to contaminate the following batch or two of coffee. Run the descaling solution through the machine as you would water if you were brewing coffee (without using grounds, of course). After you do so, run several batches of clean water through the machine—especially if using vingar.
Periodic descaling is necessary for whatever components heats mineral-bearing water; this includes electric kettles. The frequency depends upon the mineral content of the brewing water and how often you use the equipment, but is rarely more than once every few months. Descaling is rarely neccessary for components that do not themselves heat water (e.g., standard French presses).
4.3.2 Removing coffee stains
Approximately every two weeks, all equipment that comes in contact with brewed coffee should be cleaned with hot water and a very small amount of detergent (these are usually alkaline, though the degree will vary by brand). Coffee oils cannot adequately be removed with water alone; nevertheless, failure to rinse after each use will necessitate more frequent cleaning with detergant. Most brands of detergent generate of lot of suds, so use only a few drops per pint of water or you will have to do a lot of rinsing; likewise, since the taste of detergant is generally more tenacious that vinegar, it is vital that you thoroughly rinse the items. Cleaning efficacy can be increased by adding a few teaspoons of baking soda (not baking powder), thereby boosting alkalinity; in many or even most instances, baking soda alone will suffice and make rinsing simpler.
Items that can be fully submerged should be, otherwise, fill the carafe with the solution. Allow to soak for fifteen to twenty minutes and rinse thoroughly. Extremely dirty items may require long soaks (several hours or overnight) in the alkaline solution, rinsed, and perhaps followed by one or more shorter soaks.
The new oxygen-based cleaners work wonderfully for cleaning off coffee stains, especially from cloth filters, but they can stain or damage plastic and aluminum surfaces and may damage fine-mesh metal filters (especially if old and worn).
Only those items that come directly in contact with brewed coffee need to be cleaned this way. The water heating chamber of an autodrip machine, for example, only needs to be descaled—and since it cannot easily be rinsed out, adding detergant to one is not only unnecessary, it'll cause no end of frustration from soapy-tasting coffee.
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©2003, 2004, 2005, 2006 by Scott Rothstein
May be quoted in part, with attribution and links to this site.