Pierce's design was later improved by U.S. appliance engineers Ivar Jepson, Ludvik Koci, and Eric Bylund of Sunbeam in the late 1930s. They altered the heating chamber and eliminated the recessed well which was hard to clean. They also made several improvements to the filtering mechanism. Their improved design of plated metals, styled by industrial designer Alfonso Iannelli, became the famous Sunbeam Coffeemaster line of automated vacuum coffee makers (Models C-20, C-30, C40, and C-50). The Coffeemaster vacuum brewer was sold in large numbers in the United States during the years immediately following World War I.
In France, in about 1710, the Infusion brewing process was introduced. This involved submersing the ground coffee, usually enclosed in a linen bag, in hot water and letting it steep or "infuse" until the desired strength brew was achieved. Nevertheless, throughout the 19th and even the early 20th centuries, it was considered adequate to add ground coffee to hot water in a pot or pan, boil it until it smelled right, and pour the brew into a cup.
Once you start brewing, it makes a really, really good pot of coffee. Our taste test revealed the OXO On 12-Cup coffee was “dark and strong” and appealed to the more traditionalist coffee palates. The great flavor comes from the brewing process. The OXO machines have wide shower heads with multiple ports through which water streams, dispersing it evenly throughout the brew basket. Lots of other coffee makers spout water through just one hole, or through shower heads with a smaller radius, which can increase the chances of uneven extraction.
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.