Like a lot of “foodie” types, I read Cooks Illustrated. I’m not a subscriber but I scan each issue for recipes. Naturally, when they covered coffee brewers I had to read what they said. Technivorm’s Gerard-Clement Smit told me he was excited as they’d just chosen his unit as their best choice. That’s a good start. Consumer Reports has never, ever really chosen a decent coffee brewer as a Best Buy. Right away, I thought that someone credible might be reviewing if they recognize the Technivorm. How about the rest of the review?

Well, I have not yet reviewed every brewer they did, so I’ll reserve judgment unit per unit. But, I have a few quibbles with the big picture. I believe Cooks Illustrated did three tests: an objective temperature test, a brewing time measurement and a subjective taste panel evaluation. They did not identify who did their tests, but it’s a reasonable start and Consumer Reports has never identified any but a subjective panel test, so Cooks is to be commended for at least including two real tests.

In appliance theory, the time and temperature are perceived useful because it is easy to taste that the amount of time it takes and how hot the water is are the two major factors to extraction. But, in our desire to make things measurable we sometimes make things too easy. Consider fact that, according to Cooks Illustrated standards, they would never have chosen several of my favorites and one particularly well-regarded coffee brewers as best buys because they don’t meet those standards very well is interesting.

I looked for the French press measurements but they were nowhere to be seen. Sure enough, the brewing time is set by the user, so that’s understandable. But, how about brew temperatures? Does anyone but me measure the French press’s brewing temperature? And, I’m assuming we’re all following the longstanding practice of boiling water, letting it stand for a minute off-the-boil and pouring. It might be instructive because it explains my theory; that is that temperature is number three of the three brewing parameters that should be measured.

There, I’ve said it. And, now that I’ve said that, I’ll list what I think are the factors, in order of importance, for a coffee brewer:

Brewing contact time – we want to know just how long the hot water is in contact with the grounds. With some brewers this is easy. You can simply pour hot water into the French press and start a stopwatch, press the top down and stop your timer. In a drip brewer, you must factor in a delay, sometimes up a minute after you turn it on and the last water drips through. Also, some automatic drip makers actually stop from time to time during brewing, either to allow their heaters to recharge their energies or as designed to offer the grounds a chance to swell up and rest between pulses; some connoisseurs think this gives a better extraction, particularly with fresh coffee, but it makes timing the contact time a more complex procedure. But, contact time is the single most important factor in the final taste in your cup. Too short, and it will be underdeveloped; too long and it will be overextracted and bitter.

Grounds saturation – how well saturated are the grounds in your coffee brewer? Consider what it’s like when you take a shower. There is a fixed head above you (most commonly) and you move about to make sure every inch of you is properly cleaned and rinsed. Coffee grounds cannot likewise adjust their position during brewing. It is the role of the designer to make a showerhead that is designed to saturate the grounds thoroughly from beginning to end of the brew cycle. It becomes particularly challenging as consumers begin using larger grounds portions as they discover the joys of full-flavored coffee. Often the showerhead is simply a drip spout or it sprays at a midpoint in the grounds bed, hoping that the water will eventually fill and cover all the grounds. Fresh roasting and fresh ground exacerbate the situation because fresh coffee de-gasses carbon dioxide as it’s brewing, interfering with extraction chemically, but also causing the grounds to physically expand, even making them a larger and more difficult-to-cover target for the showerhead. This is THE notable flaw in many brewers, even those who reach the industry’s recommended water brewing temperature. Methods such as French press and vacuum have maintained cultish favor with connoisseurs precisely due to their inborn skill provide great grounds saturation.

Brewing temperature – the single most overrated attribute of a coffee brewer is its brew temperature. Am I saying it’s unimportant? Absolutely not, but it is in third place. Why is it number 3? I suppose because it’s the easiest to measure. If you want my honest opinion based upon years of observing coffee brewers and measuring the brewing temperature, it is that any brewer that brews between 180 and 212 CAN conceivably brew very good tasting coffee, PROVIDED the contact time is kept under six minutes AND the grounds are well and equally saturated.

Take a few examples. Have you measured your French press’ temperature lately? I think you might be surprised at how low it is, in consideration of the Specialty Coffee Association’s recommended brewing temperature (200 degrees Fahrenheit +/- 5 degrees). If you don’t like the press (and Cooks Illustrated didn’t) it is likely due to other factors, such as the amount of grounds left in the cup (I prefer paper filtered “cleaner” coffee – press coffee is too muddy for me). Most press brewing is done well under 195. Generally, if used according to directions, the press will drop off below 195 within a minute of pouring the water into it. It regularly ends contact time at under 185. I once heated a press during operation to maintain 200 degree contact heat and I thought the coffee tasted worse for it. If you are fond of manual drip brewing, such as Melitta’s or Chemex, the results are similar. You continuously pour off-the-boil water into the grounds and wait for the water to run through the grounds bed. If you chart the temperatures over the course of manual drip brewing, it will be series of low hanging telephone lines, each dipping well below 195. If it were not for having proper vacuum preparation coffee, I’d be inclined to regard below 195 temperatures as superior.

Speaking of the vacuum, it is my considered belief that the original industry brewing standards adopted by the SCAA and other trade organizations was based upon observing the once-standard vacuum machine as a peerless example of good brewing. So, the standards were simply reverse-engineered to become THE standards. While at first glance, this seems sensible, it is too confining and it sends well-meaning appliance designers in the wrong direction. Again, my observation is that there are various good and interesting coffee flavors extracted throughout a wide range of temperatures. Some years ago I was a member of the Specialty Coffee Technical Standards Committee. I challenged our group that we’d recently denied certification to Kitchen Aid for their 4-cup maker because it only reached about 190. Meanwhile, we were enjoyably sharing our Chair Kevin Knox’s French press coffee (Kevin at the time ran Allegro Coffee’s roasting operations) which I pointed out was brewed at a temperature in line or below the Kitchen Aid unit. Is there anything wrong with a solid 200 degree contact time? No, and it might arguably extract some of the very finest flavors from coffee. But, there are credible machines that produce excellent tasting coffee (above and below) this range. Meanwhile, there are machines that get the water to the right temperature but fail to keep contact times between four and six minutes and/or fail to get all the grounds consistently wet. Give a choice between a machine that is outside the temperature range or one that either does not get all the grounds wet or takes longer than six minutes, I’d choose the one that’s temperature is non-standard.

So, Cooks is to be commended for trying to follow industry standards and indeed for even emphasizing the importance of a good brewer to coffee taste. But the industry needs to reexamine the standards as well as their order of importance, given the new consumer interest in fine coffees and how to enjoy them at their best.