Fahrenheit 200: Coffee's Best Friend

Photo by larryvincent/FlickrCC

OK, back to coffee. Until recently, I've been preoccupied with preparing for the Zinfandel Advocates & Producers 19th Annual Zinfandel Festival in San Francisco, where we poured Baldwin Rattlesnake Ridge 2008 Zinfandel to critical acclaim.

When I promised more on drip coffee, I was thinking about the difficulty of achieving proper brew temperature in automatic drip makers. I wrote briefly about controlling brewing temperature using the manual method on December 1. It's a crucial element in making good coffee, so here's the long version.

When you use a simple drip pot or filter cone, you boil the water and pour it over the coffee, ensuring that the temperature is in the proper range of 195 to 205 F. But that's not how most people make drip coffee. For decades, the bestselling appliance in the U.S. was the electric drip coffee machine. They are ubiquitous. There are so many brands and models, it's nearly impossible to make sense of them. The criteria of evaluation are broad: price, features such as an internal clock that automatically starts the brew, thermal carafe, the filter type, the looks, the color.

For most professionals, the first criterion is brewing temperature. If the machine cannot achieve and maintain proper brewing temperature, it shouldn't be considered. A lower brewing temperature causes two negative effects: insipid coffee, the direct result of lower temperature extraction; and bitterness, the result of a longer brewing time.

Inexpensive machines have an undersized inline water heater (not a tank, as in a commercial machine). The water flow is reduced, and the brew cycle takes longer. Some machines take 12 minutes to brew at a sub-optimal temperature. The result is less flavor and more bitterness.

Commercial drip makers can usually reach 200 F and will brew in about four minutes. Only a handful of home machines can come close. A common standard for good home machines is proper temperature over a brew cycle of six minutes or less.

Despite many attempts by manufacturers over the years, few machines could achieve these essential criteria, but change has come. In December 2009, Consumer Reports rated 40 coffeemakers on several criteria. I was quite encouraged by the number and price range of models that could sustain proper temperature and brew within the six-minute standard. Thirteen of the 40 listed makers could pass the crucial test. They ranged from Mr. Coffee JWX27 and Michael Graves 40304 ($40) to the professional standard-setter, Technivorm KBT741, at $265.

Unfortunately, the Consumer Reports Web site requires a subscription. Perhaps you or a friend retains old copies of the magazine before recycling. A caution about these ratings: my experience with Consumer Reports is that they are excellent at objective tests. They can measure temperature and duration without fail. I find them less valuable when they are reporting on subjective criteria, such as convenience. Of even less utility is their organoleptic reporting, which is inconsistent and reflects too narrow a group of tasters. I say this even though our coffee from Peet's has finished first in their review of coffees.

Before buying a home brewer, I would thoroughly research brew temperature and duration. If necessary, I would buy a machine that I could return. Then I'd take it home, and test it with just water, to make for an easier return if it failed. The best type of thermometer is a mercury thermometer, which I have found online for as little as $3.40. They react quickly to temperature, though it's better to pre-warm the thermometer to the temperatures you'll be testing. Dial thermometers or digital thermometers that have probes don't heat up quickly enough for accurate measurements.

As with any cooking, a little preparation can significantly improve the result. Be sure you get a machine with a cycle that's sufficiently fast and hot—that's more important than style and even cost. Then, of course, follow all of my other advice.