The Breville machine was also the only semi-automatic model to produce a velvety, well-incorporated foam. The consistency with which it incorporated air made for a beautifully textured latte—and our coffee expert was even able to make some latte art with it (something that was impossible with the air bubbles from other models, including the Gaggia and all of the less expensive machines).
The Breville is technically a semi-automatic espresso maker, since it requires you to dose and tamp your own shots, but we found it more forgiving than true automatics. The Breville’s dual-wall filter baskets (in addition to two standard single-wall baskets) add extra pressure, providing a little forgiveness for beginners’ mistakes in either grinding the beans or tamping the shot.
If you want a fully automatic machine that makes a great espresso, the Jura is a great option. It has a built in burr grinder, meaning you'll get the freshness of a semi-automatic machine. It allows you to choose from three cup sizes, meaning it will brew a coffee, an espresso, or a ristretto (a short shot). You can also choose the strength of your coffee, selecting between dosage sizes of 8–10 grams. The machine has a relatively easy to use touch screen. And, the spout that dispenses the coffee has an adjustable height, making it possible to maximize your crema depending on your cup size—the closer to the cup the spout, the better the foamy creaminess will be on top. It includes a milk steaming compartment and steamer, which creates a creamy, well-incorporated foam.
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.
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.
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.