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.
“This is the same coffee maker that I bought years ago. And it’s even the same price. Yep — they do still make things like they used to. And they last forever. It’s super simple, super reliable, compact, and cheap. There are a lot of places where we can spend money, but a simple cup of coffee doesn’t have to be one of them. Once you get the amount of water and coffee figured out to your taste — simply do that. No K-cup, nothing to recycle, fits the car cup holder. And the coffee stays hot in the mug.”
If you make your coffee at home, you want to make sure that you’re getting a great-tasting and convenient cup of coffee whenever possible. The best way to do this is to invest in the right equipment. In the home, no piece of coffee equipment is more important than the coffee maker. In most cases, you add the water and the grounds, and the coffee maker takes care of the rest. With many types of coffee makers available on the market today—including French presses, stovetop makers, pour overs and traditional drip coffee brewers—it can be difficult to choose the right one for your needs.
‡Pre-Infusing: Pre-infusing is a technique where the dry coffee grounds are initially saturated with hot water, allowing a “bloom” of carbon dioxide to escape. This 45-second(ish) process puts hot water into contact with more surface area around each ground throughout the brewing process, as it’s no longer competing with the escaping gas bubbles. It can improve the quality of the final product, since this more uniform contact creates a more even extraction. It’s a feature that six of the 10 pots we tested incorporated into their designs — as well as all four of our top picks.
Programmable coffee makers exist to make the brewing process as painless as possible. Outside of maybe grinding your coffee beans, the drip coffee system will use optimal water temperatures of around 205 degrees Fahrenheit or 96.11 degrees Celsius for maximum extraction of the ground coffee beans. The best automatic coffee maker will seamlessly reach this temperature within minutes of the brewing process.
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.