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.
“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.”
Whole bean coffee that you grind yourself is preferable to pre-ground, too. The bean’s exterior traps and protects all of the delicate, volatile, and water-soluble oils that give coffee its flavor. As soon as you break the protective shell, it’s easy for the flavor to get contaminated, and much of the aroma escapes as soon as the oils are exposed to air.
Bunn-O-Matic came out with a different drip-brew machine. In this type of coffeemaker, the machine uses a holding tank or boiler pre-filled with water. When the machine is turned on, all of the water in the holding tank is brought to near boiling point (approximately 200–207 °F or 93–97 °C) using a thermostatically-controlled heating element. When water is poured into a top-mounted tray, it descends into a funnel and tube which delivers the cold water to the bottom of the boiler. The less-dense hot water in the boiler is displaced out of the tank and into a tube leading to the spray head, where it drips into a brew basket containing the ground coffee. The pourover, water displacement method of coffeemaking tends to produce brewed coffee at a much faster rate than standard drip designs. Its primary disadvantage is increased electricity consumption in order to preheat the water in the boiler. Additionally, the water displacement method is most efficient when used to brew coffee at the machine's maximum or near-maximum capacity, as typically found in restaurant or office usage. In 1963, Bunn introduced the first automatic coffee brewer, which connected to a waterline for an automatic water feed.
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.