Coffee quality depends on a combination of factors. Fresh beans and high quality beans are obviously desirable, but the highest quality beans are all but useless if stale. Clean good-tasting water must be used, and the coffee must be brewed with clean equipment at the proper temperature for the proper amount of time.
For coffee brewing, the Specialty Coffee Association of America (SCAA) prescribes a water temperature of 195 - 205 degrees F. Avoid boiling then cooling the water to the proper range, or at least letting it boil for more than a few moments; boiling hot water rapidly loses dissolved air and will taste flat. If the water is too cool, the brew will be sour and underextracted. The temperature range during brewing should not vary by more then a few degrees, or extraction will not be optimal. Temperature loss often occurs as a result of heat absorption by the equipment itself (for example, if an espresso machine's portafilter is not kept warm between shots by storage in the machine) or into the atmosphere (as in a uninsulated glass French press during the approximately four minute steeping period). Pre-warming the equipment or insulating it, respectively, will solve these problems.
Coffee is 98.5 to 99 percent water, so water quality will critically affect the resultant brew's taste. When making coffee, you should only use water that tastes good enough to drink straight. As a result, the best cups of coffee are made with filtered tap water or bottled water. Carafes or sink-based filters will likely perform better and have a lower per-gallon cost than the modest charcoal filters that some manufacturers include with their auto-drip machines. Do not mistake distilled water for filtered: the former is missing minerals that contribute to the water's taste and aid in extraction. The water should be fresh; it it has been sitting too long (or has been heated then cooled), it will be missing the dissolved air that is an important component of the water's taste.The water should also start cold: hot water has lost some of its dissolved air, and may have picked up minerals or solubles from your pipes.
How much ground coffee should I use?
A standard "cup" of coffee uses six ounces of water. The SCAA's standard measure of ground coffee for this quantity of water is two tablespoons.
For those who find that the two tablespoon/6 ounce ratio produced too strong a cup, simply reduce the quantity of coffee used until the desired strength is reached.
Recommendations to grind more finely and thereby use less coffee are simply wrong. Grind fineness is related to steeping time; using less but finer coffee will make the resultant product bitter; using less coffee under these circumstances will make a weak, bitter cup.
How do I keep coffee hot?
Optimally, brew a fresh batch whenever you want coffee. To keep coffee hot for shorter periods of time, or for travel, use a thermally insulated container; an enclosed container will reduce the loss of the aromatics that constitute an essential part of the overall flavor. Insulated containers with glass internals, though somewhat delicate, have the least effect upon the coffee taste, followed by good quality stainless steel. Coffee with significant residual sediment, such as coffee brewed in a French press, fares less well when kept hot for extended periods; the sediment continues to extract, making the coffee bitter.
Optimal flavor is obtained by holding the coffee at high temperatures, at least 170 degrees Fahrenheit.
Direct heat—e.g., via a warming plate—should not be applied to brewed coffee, at least not for more than few minutes; continued heating will make the coffee bitter. This issue is primarily a concern for autodrip coffee makers; choose a model that dispenses into an insulated carafe over one that uses a warming plate.
Reheating coffee in the microwave is controversial; the key issue may be the uneven heating microwaves are known for. There are those who theorize that parts of the coffee that overheat may taste unpleasant, thereby spoiling the cup as a whole.
In theory, the best containers are simply those that keep the coffee hot and do not add flavors of their own. Heavy, pre-warmed ceramic cups probably serve those criteria best.
Author: Scott Rothstein
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