- Created: Sunday, 14 December 2003 11:15
- Written by colin
The Guide to Coffee Brewing (originally published - June 1995!)
Brewing the perfect cup of coffee can be simple. The process of brewing coffee involves heating water (to the correct temperature) and passing that water through fresh ground coffee in a certain amount of time. Thus the four major variables of the brewing process are water, heat, the ground coffee, and brewing time.
Coffee is over 99% water and it is important to consider the origin of your primary ingredient. For the most part, the average home brewer uses water straight out of the tap. Even if your tap water tastes fine, it may contain impurities that will cause the coffee to have a flat or dull taste. If you must use tap water, be sure to run it for several minutes so that the stale water which has been stagnant in the plumbing is flushed away. Better yet, do what I do. Use bottled filtered water available in gallon containers from groceries. Keeping four or five containers on hand in the event of a natural disaster or emergency is also a smart thing. At least when you buy bottled you have a good idea of what you are getting and that eliminates one step (or impediment) towards the perfect cup.
Boiling water should never come in contact with fresh ground coffee. The ideal brewing temperature is between 190 to 205 degrees F. This is one of those classic reasons why percolating the coffee or boiling it repeatedly over the campfire, cowboy style, is always a bad idea. The boiling produces unpleasant tasting substances and destroys whatever good flavors there are in the brew.
The grind you select or how you grind your coffee with depend entirely on the method you use. In traditional drip pots and electric drip brewers, a fine grind is usually called for. In Press, Bodum, and Melior carafes, a coarse grind is always prefered.
A good rule of thumb: You cannot rush a good thing. There is no such thing as a 'fast' coffee brewer. A good drip brewer will turn out 4 to 6 small mugs of hot coffee in about 5 to 7 minutes. Why, you ask? The ideal rate of extraction and the brewing temperature are kind of tied together. Hotter water extracts more of the qualities you are looking for but too a point. Too hot and you have trouble, too cool and you have a thin and tepid brew.
-- Drip brewing
The drip method of brewing coffee is the most popular due to its ease and convenience. While it does not produce French-press quality coffee, it is certainly very good if done properly.
As with the French press method, you should use two heaping tablespoons of ground coffee for every 6 to 8 ounces of water. This may seem strong to some drinkers, but it is the amount required to bring out all the unique tastes that coffee has to offer.
The coffee should be ground fine because most drip brewers have a short brewing cycle. Most home grinders should be set to nearly their finest setting to get the proper grind.
Fact - The degree of grind, when brewing filter drip style, is like a speed trap for capturing the right brew time. The finer the grinder, the slower the brew cycle. This method of controlling brew time puts you in the driver seat.
Because there are dozens and dozens of drip machines on the market I cannot say too much about any particular machine. Some important rules:
You get what you pay for. The best brewers concentrate their resources on heating the brew water to the right temperature and getting it to the ground coffee in a evenly distributed way. Good brewers do not have warming plates. Warming coffee or re-heating coffee is destructive.
The best brewers on the market brew their coffee hot and into a thermal insulated carafe. Coffee is very sensitive to oxygen and will oxidize quickly when exposed to air.
After the coffee has been brewed, you should serve it immediately. If any is left over, store it in a thermos bottle - not on a burner or hot plate. If coffee is left on a heated surface for more than a few minutes, the aromatic compounds that make it taste good will begin to break down and the water in the coffee will evaporate, leaving behind a soup of bad-tasting chemicals!
--The facts about the coffee bean
Do not store coffee in the refrigerator. Do not store coffee in the freezer. We suggest that coffee be kept in an airtight container and stored in a cool, dark, dry place.
Putting beans in the refrigerator is not good, even if you use an airtight container. Moisture is the enemy of roasted coffee as is oxygen - the flavor "oils" in roasted coffee are very complex and delicate, volatile water soluble substances that moisture immediately dilutes and odors taint. Refrigerators tend to be both damp and full of odors.
Fact - Whole coffee beans make a remarkable air freshener or fridge deodorizer.
If you have way more coffee than you need, freezing the beans in a double zip lock bag is an alternative to the fridge. A better policy is to buy what you need, generally 3 or 4 days worth at a time. Consider this: Whole bean coffee, after roasting, is truly fresh for 5 to 7 days. After grinding, coffee is fresh for a few hours.
Dark-roast coffees do not freeze well. Completing a dark roast drives volatile oils closer to the surface of the bean. When frozen, these oils congeal and do not reconstitute.
If you do not have a grinder, and the ground coffee is not to be brewed for a week or more, and the container is airtight, then freezing the ground coffee is a last ditch option.
How long will my coffee last?
Roasted whole coffee beans keep for a week before they should be consumed. Stored in a dry, airtight container to prevent contamination or contact with moisture, roasted whole bean coffee holds its flavor and aroma for about a week.
--Brewing alternatives and grinding
There are many methods of brewing coffee. We have examined the most popular method in North America, the electric gravity brewer using paper filters. Consider if you would, the mystery of the French Press, Melior or Bodum!
The French press method yields the best flavor for non-espresso coffee because there is no paper filter to remove the large colloids that impart the coffee's flavor. However, this method leaves a good deal of sediment in the final cup which is unattractive to some drinkers and may be a source of catalyzed cholesterol according to some recent studies.
I use a burr grinder for the task of preparing the coffee. I do not use the cheap rotary grinder that is common in many households. The trade off is this: A rotary grinder produces an imprecise mix of fine and coarsely ground coffee leading to over extraction of the fine coffee and under extraction of the coarse coffee. It is also somewhat more wasteful. It is important to get a fairly coarse grind when using the press and a rotary is rarely up to the job. Do yourself a favor. Spend $60, or more, dollars or so and get a good burr grinder. It will pay for itself in the long run.
--What is the French Press, Bodum, Plunger Pot, or Melior?
The French press is a glass cylindrical pot that has a plunger affixed to the lid so when you push down on the top of the plunger, it forces a fine wire mesh through the pot to the bottom. You put the ground coffee into the pot and pour hot water over it. After the coffee steeps for several minutes, you put the lid in place and push the plunger down, forcing the spent grounds to the bottom of the pot while the brewed coffee remains above.
Done properly, this method produces a very full bodied brew. Done carelessly, it produces passable coffee that retains a certain rustic charm nonetheless.
Since you will be able to control both the temperature of the water and the length of the brewing cycle, you should use coffee grounds that are significantly coarser than what you use for drip coffee. Put two to three tablespoons of ground coffee into the press pot for every six to eight ounces of fresh water you intend to use.
Brewing instructions for the press-pot:
Boil the water (in a kettle). Take the water off boil when it is ready. Toss in your coarse ground coffee. Take a deep breath. Toss the water onto the grounds.
Optional: pre-soak the grounds with hot water to: Pre-infuse the water & prevent scalding the grounds and damaging the delicate oils and acids.
Wait 1 minute.
Add hot water just off the boil.
Push the plunger down.
Wait two minutes.
Now enjoy this method of coffee brewing!
Colin Newell lives and works in Victoria B.C. Canada. He considers coffee a pleasant drink and is unlikely to give it up anytime soon.