A cafetiere (Coffee Plunger, French press in US English) requires coffee of a coarser grind than does a drip brew coffee filter, as finer grounds will seep through the press filter and into the coffee. Coffee is brewed by placing the coffee and water together, stirring it and leaving to brew for a few minutes, then pressing the plunger to trap the coffee grounds at the bottom of the beaker.
Let’s circle back to that extra-long brew time. There are two factors that didn’t make it an automatic “no” for us. The first is that the OXO On 12-Cup is programmable. Like our experts say, grinding coffee in advance isn’t going to make the most perfect cup of coffee. But the fact that you can program the machine’s “wake-up time” to start brewing and have coffee ready when you are takes the sting out of the wait.
On August 27, 1930, Inez H. Pierce of Chicago, Illinois filed patent for the first vacuum coffee maker that truly automated the vacuum brewing process, while eliminating the need for a stove top burner or liquid fuels. An electrically heated stove was incorporated into the design of the vacuum brewer. Water was heated in a recessed well, which reduced wait times and forced the hottest water into the reaction chamber. Once the process was complete, a thermostat using bi-metallic expansion principles shut off heat to the unit at the appropriate time. Pierce's invention was the first truly "automatic" vacuum coffee brewer, and was later incorporated in the Farberware Coffee Robot.
It’s obvious, but easy to forget: If you don’t clean out your coffee machine’s carafe after each use with soap and water, you’ll always end up tasting a little bit of yesterday’s now-bitter brew. Thermal carafes need to be hand-washed, but all the plastic components of our top picks — brew baskets, lids, etc. — are dishwasher-safe if you keep them on the top rack.
Our brew-performance tests measure the brew temperature and contact time (how long water stays within a sweet spot of 195° to 205° F for brewing). We measure concentration using a refractometer, a device that measures the amount of coffee dissolved in each brew. Our convenience tests look at how easy it is to set timers, fill the reservoir, clean the machine, and more. And for the first time, we’re incorporating predicted reliability and owner satisfaction ratings into the new Overall Score for each model. We determine these ratings for each drip coffee maker brand using survey data collected from thousands of CR members.