Some machines use a single boiler kept at steaming temperature, but water for brewing is passed through a heat exchanger, taking some heat from the steam without rising to the same temperature. Although the water for brewing remains at a lower range than that required for steaming milk, it is still too hot for proper coffee extraction without first cooling; thus this type of machine requires a cooling flush of 4–6 seconds prior to the first espresso pull. Once the machine is dialed into the proper temperature, as many shots can be pulled as required without refreshing. However, if the user leaves the machine idle again for some period, the flushing process will need to be repeated. The HX variety is found in many mid-range machines and many users install thermometers to assist them is dialing in correct temperatures. There is some controversy as to the temperature stability of the brewing water, since it is indirectly converted from steaming temperature to brewing temperature, rather than kept at a brewing temperature.
"A rare example of the meeting of form and function. This machine is both beautiful to look at and makes wonderful delicious espresso and cappuccino. I was hesitant to spend this much on a "coffee maker", but took into consideration what it costs to get a decent cappuccino from a cafe or Starbucks and finally gave in. Boy am I glad I did. All it takes to get me out of bed in the morning is the happy thought of pulling yet another delicious shot from this wonderful machine."
The single-serve or single-cup coffeemaker has gained popularity in recent years. Single-serve brewing systems let a certain amount of water heated at a precise temperature go through a coffee portion pack (or coffee pod), brewing a standardized cup of coffee into a recipient placed under the beverage outlet. A coffee portion pack has an air-tight seal to ensure product freshness. It contains a determined quantity of ground coffee and usually encloses an internal filter paper for optimal brewing results. The single-serve coffeemaker technology often allows the choice of cup size and brew strength, and delivers a cup of brewed coffee rapidly, usually at the touch of a button. Today, a variety of beverages are available for brewing with single-cup machines such as tea, hot chocolate and milk-based specialty beverages. Single-cup coffee machines are designed for both home and commercial use.
†Programmable Brew Time: Conventional wisdom frowns at grinding beans early and programming a pot to brew later. The aromatic compounds in coffee beans start to oxidize as quickly as 15 minutes after grinding, which causes coffee to start losing aroma and flavor. But Michael Ebert, senior consultant at Firedancer Coffee Consultants, LLC, assured us that, given the trade-offs for convenience, “grinding the night before will still make a great coffee — just not as great as it could be.” Seven of the 10 pots we tested are programmable, including three of our top picks (all but the Bonavita).
“Quite possibly the best investment I’ve made in an appliance to date. This powerful machine makes THE BEST COFFEE. I’m a coffee snob, so Keurig never impressed me, and I don’t have the space to purchase a full espresso machine. The Ninja system is compact, but offers a variety of brewing settings. Very easy to clean. Huge fan of this brand in general, and I’m so glad I made this purchase. Even comes with a travel mug.”
All the machines we tested came with either insulated carafes or glass pots with built-in warmers. Both have pros and cons. Glass pots are typically easier to clean because they tend to have wider mouths, and the lack of internal insulation means that glass pots will have a greater interior volume relative to its exterior volume — basically, it’s easier to get your hand or dish sponge into a glass pot. On the other hand, glass pots are more fragile and have to be heated from a base plate. In our tests, those base plates could even raise the temperature of the coffee, like with the CuisinArt, which can make coffee taste burnt.
A new French press is an ideal companion on a camping trip or picnic. Our sturdy versions of French presses are available in glass, metal, ceramic and other materials. Invest in your own efficient single-cup brewers with included cups and thermal mugs to create on-the-go coffee drinks for one person. Cold-brew machines and kits are other terrific options when you prefer chilled and iced coffee beverages. Remember to order plenty of filters, tampers, descaling tabs and other coffee accessories to keep your machine fresh and bright. Clean machines with the right size filters brew the best coffee