If you’re shopping for coffee at the grocery store, “check the roast date, rather than the ‘best by’ date,” says Awan. With mass market roasters, the “best by” date can obfuscate the window in which coffee beans are at their best: about 4 days after roasting, when some, but not all, of the carbon dioxide has escaped from the beans. (Too much carbon dioxide captured within beans tends to create uneven extraction, as the gas escapes — this is what pre-infusing tries to counter. Conversely, too little carbon dioxide in the bean can lead to a loss of flavor.)
The principle of a vacuum brewer was to heat water in a lower vessel until expansion forced the contents through a narrow tube into an upper vessel containing ground coffee. When the lower vessel was empty and sufficient brewing time had elapsed, the heat was removed and the resulting vacuum would draw the brewed coffee back through a strainer into the lower chamber, from which it could be decanted. The Bauhaus interpretation of this device can be seen in Gerhard Marcks' Sintrax coffee maker of 1925.
CR’s take: For $80, this Mr. Coffee 12-cup drip brewer is surprisingly stylish. Its airy design sets it apart from the blocky shapes common to the category. This model earns a rating of Very Good in CR’s brew-performance tests and makes a full pot in just 9 minutes. It offers brew-strength control, programming, and a permanent coffee filter. With its performance and striking appearance, you might not mind having it out on the counter—especially in a kitchen with a stainless fridge and range.
It can take a little while to get to know the ins and outs of a new coffee maker. In CR’s labs, each drip coffee maker we test brews roughly 65 cups by the time our engineers are through with it. And brewing is just one of many aspects we look at. We test for handling and convenience, too, so you can choose a model that helps you sail through morning madness.