This testing was designed to highlight the difference in how each machine extracted its coffee grounds. Remember, extraction is tied to water temperature, how long the grounds had to steep, and how evenly that water is distributed in the brew basket. (Depending on how the machine distributes the water and the shape of the basket, any particular ground may or may not receive the same amount of time in contact with water — thus any individual grind may be over-extracted, under-extracted, or just right.) Properly extracted grounds would have a balance of notes and aromas, from slight hints of acid to a pleasant amount of bitterness.
For example, if your coffee tastes a bit salty or sour, the grounds are under-extracted, which can be remedied by a finer grind. But what if only some of your grounds are too coarse, and others are too fine – and maybe some are just right? Having uniform grind size throughout your brew basket makes it easier to isolate and adjust this variable in order to get the level of extraction you want. The only way to achieve that is with a burr grinder. Miller — as well as a handful of our other experts — recommends the Barazata Encore Coffee Grinder ($129).
For many of us, the daily grind can't begin until we've had that first cup of piping hot coffee—so the right brewer is at the top of the list. The most basic coffee makers make at least a decent cup, but a little more money buys conveniences such as programmability, a thermal carafe to keep coffee hot longer, settings that let you adjust brew strength, and more.