Drip Coffee Makers 9/2008
Most models turn costly beans into mediocre coffee: too weak, too flat, or too bitter. What’s so hard about making a decent drip coffee maker?
In this age of Starbucks, Americans have gotten much more sophisticated about the complexities of coffee flavor. Now when we make our coffee at home, that old Mr. Coffee on the counter—never all that great to begin with—increasingly doesn’t measure up. As we surveyed the latest models on store shelves, we wondered if manufacturers might have caught up with our coffee obsession and finally developed an automatic drip coffee maker that can produce a terrific brew.
From previous tests, we knew that a thermal carafe would be essential; the usual hot plate under a glass carafe starts turning fresh coffee acrid in a matter of minutes. We found eight brands with thermal carafes and at least a 10-cup capacity at prices from $47 to nearly $300. Most were programmable, meaning you can fill them with coffee and water and set the time you want the pot to turn itself on. Two came with an attached burr-style coffee grinder. With hope—and more than 30 pounds of freshly roasted, house-blend coffee beans from Stumptown Coffee Roasters in
Portland, Oregon—we set to work.
Better Brew
Brewing a full pot in each machine, we asked tasters to judge the coffees’ aroma, body, complexity of flavor, level of bitterness, and overall appeal. Our hopes for the new generation of coffee makers were quickly crushed. Most of those eight stainless steel machines made the same kind of mediocre coffee we’ve come to expect: bitter, weak, or one-dimensional.
What was the problem? Aside from using fresh, high-quality coffee beans and good-tasting cold water, the two most important factors in making good coffee are the water temperature as it passes through the grounds and the length of time the grounds are exposed to the water. These factors determine which of the more than 1,000 volatile flavor and aroma compounds identified in roasted coffee beans make it into your cup and which get left behind (only a limited number of them—approximately 30—produce the best-tasting coffee). Studies have shown that the most
flavorful, aromatic compounds are released by water between 195 and 205 degrees Fahrenheit, at a brew time of six minutes, for drip coffee makers. The ideal cup of coffee contains 18 to 22 percent suspended solids extracted from the ground coffee. Too fast a brew time and the extraction of solids will be less than 18 percent, and your coffee will be weak; too slow a brew time leads to overextraction (more than 22 percent suspended solids) and a bitter brew. If the coffee maker is too slow and the water is not sufficiently hot, you can even wind up with coffee that is both weak and bitter.
We made more coffee, this time measuring the water temperature throughout the brew cycle. And here we made a key discovery: Most of these machines were too cool, spending most of the brewing cycle struggling to bring the water into the right temperature range. Many didn’t reach the correct temperature until the last minute or two of brewing—and then kept climbing, scorching the grounds as the last few cups dripped into the carafe.
Next, we timed three pots in each coffee maker with a stopwatch and averaged the results. Once again, our lousy coffee could be explained: Most of the machines never reached that ideal time frame for water to pass through the coffee grounds, though two came much closer than the rest. The slowest machine took 18 minutes to make one pot of very bitter coffee. The fastest took just four minutes, and tasters found its coffee weak, thin, and flat.
Tasters’ Choice
How can manufacturers keep getting away with these crimes against good coffee? They know consumers can’t taste the coffee before they buy the machine; most choose a coffee maker based on looks and price. New models are dressed up to be enticing, with graceful carafes, backlit digital displays, and multiple features. Why can’t the flavor match up? “To sell their coffee makers competitively, these machines have to be made cheaply,” said Mané Alves, chair of the technical standards committee for the Specialty Coffee Association of America. “And the most expensive part of the coffee maker is the heating element.”
In the end, only one coffee maker stood out in our tests as exceptional. The Technivorm Moccamaster (model KBT741), made in the Netherlands, consistently brewed smooth, full-flavored coffee that our tasters ranked highest. Tellingly, it was the only model to get close to the ideal six-minute brewing time, averaging 7 1/2 minutes to completely finish dripping, though the water was fully dispensed within six minutes. Unlike any of the other coffee makers, its internal heating element brought the brewing water to the correct temperature range within seconds and kept it there through the brewing cycle.
It turns out that in contrast to most coffee maker heating elements, which are made of aluminum, the Technivorm’s heating element is made of far more expensive copper. In coffee makers, the heating element usually runs alongside a tube containing water. As the cool water drips down from the tank, it passes through the heated channel, then boils up to the top of the machine, and finally drips down onto the grounds. A copper heating element has higher thermal conductivity than aluminum, meaning it is more responsive and can reach a higher temperature more quickly.
The Technivorm is also more powerful, operating at a higher electrical wattage than most coffee makers—with 1,400 watts compared to the average 900 watts of the rest of the lineup—making its brew time correspondingly more efficient.
The $240 Question
Its sophisticated internal workings aside, the rest of the Technivorm is simple, with a cone to hold the coffee and a nine-hole sprayer to disperse water evenly. A switch lets you stop the flow of water to pour a cup. There’s just one problem with the Technivorm—its price. Could we really justify spending $240 when we know that great coffee can be had through far cheaper methods? To make sure, we compared coffee made in the Technivorm to coffee from a French press, the method favored by many coffee connoisseurs.
(We used the Bodum Chambord, which sells for $39.95.) To our surprise, while our tasters enjoyed the French press coffee’s rich aroma and flavor, the Technivorm coffee won the day with even better flavor—and with no need to go through the French press’s multiple steps of separately heating the water to 200 degrees, then pouring, stirring, waiting four minutes (according to manufacturer instructions), and pressing.
The Technivorm’s price tag is high, but its consistently full-flavored, smooth brew—made with all the convenience of that old Mr. Coffee—will pay for itself when you start skipping a few trips to Starbucks.
Searches pulled up pretty old threads; any current rec's on coffeemakers? Maybe from Cook's Illustrated testing? My coffeemaker's an el cheapo Black & Decker SmartBrew; it never got the coffee as hot as our old Krups but it did well enough till the Teflon plate began losing all its Teflon--and the lid falls off the carafe, and it has an occasional random leak of coffee onto the counter, and now the coffeemaker lid itself falls off whenever I try to load the grounds & water. The only ones I know I don't want are the Cuisinart Grind 'n Brew (I've heard they're deafeningly loud & not so efficient anyway), and the KitchenAid (we tried a red!!
one, but the circuit board in the control panel went out just a few weeks after we bought it). Thanks!
Reply With Quote
. We have had the cheapies but they have died quickly. Think we will stick to our C GnB, it is the best we have had so far. Guess I didn't help you at all. Nevermind 
Originally Posted by Jazzmatazz49
