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ty-control supervisor, explains that using oak-wood-fed flames is not only part of the tradition of coffee roasting, but also lends something more of an art to the process—which, by the way, tests the idea that where there's fire, there's smoke. "The temperature in the firebox where the wood is burning is somewhere around 1,000 degrees," he explains. "That's a very clean heat, with very little smoke. The drum is a double-walled drum so the flame should never really reach the drum, but if it does it's really only reaching the outer layer. The drum tem- perature is about the same as a conventional roaster, 400, 500 degrees [Fahrenheit]." Roasting with wood carries an additional host of considerations, since the wood itself is as much a changing natural ingredient in the process as the beans themselves are. "I think first of all you need a really reliable source of wood," John explains. "It has to be seasoned properly: If it's too fresh, then it has too much moisture and it smokes; if it's too dry, then it burns really fast. It has to have the right mois- ture content, which is about 15%. The wood is really important." s One of the most significant of the variables involved in roasting is de- termining not only a roast level—how dark or light to take a particular batch—but also the roast profile, or the avenue by which that light- ness or darkness is achieved. Say I want a so-called "medium roast" on my coffee: Should I turn up the heat and brown those sugars in a short period of time, or should I turn the heat down and let the roast develop slower? While the end product might achieve the same rela- tive result on a color spectrum, the effect of the roasting procedure, or the curve, can be dramatically different flavors in the cup. Ian from Topeca Coffee has a particular strategy for assigning a profile to any new coffee the company buys. "We have a kind of gener- ic profile for different densities that we start with—maybe a higher charge temperature for a hard bean, push it with a little heat up front so we can get some good sugars cooking, some caramelization, those generic profiles come out of years of trial-and-error." he sys. "We use those first, I'll cup them, and if I'm satisfied with it, great, we don't need to change anything just yet. But if it's lacking, maybe the body, or the acidity that was really great in that sample is a little muted, or maybe it got a little too blasted and there's some more carbonization, then I'll work backwards and say, 'Why does this taste like that?' May- be it needs more airflow in the beginning or the end. Maybe it needs a higher charge temp or a lower charge temp. Those kinds of decisions will be made after that first cupping, and then you cup it again. It's this constant roasting, cupping, roasting, cupping." Even all that work, however, doesn't mean the process is ever really over. "You finally nail it, after you've been working on it for a week, two weeks," Ian continues, "and then, Oklahoma being Oklahoma, you've got a week of 20% humidity and it's below 30 degrees. And then you're like, well, now I have to start all over because the coffee's not going to taste the same using that same roasting profile." After a batch is finished and cooled, a roaster might then take a sample of the degree of darkness using an Agtron machine—a spec- trometer that uses nearly infrared light in order to detect the precise level of the roast. An Agtron scale is used to quantify and compare those darknesses: A 65 on the scale would be rather light, used for cupping pre-ship samples for instance; a 45 on the Agtron scale would be considered something akin to "French roast." (Seemingly counter- intuitively, the numbers get lower the darker the coffee.) Consistency, while sometimes difficult to achieve, is absolutely key when trying to pump out a batch-by-batch product like coffee: Most roasters will chuck a batch if it falls outside of a window of acceptable variation on the Agtron scale, which can be a tremendous drain of resources. Again, however, consider the many factors that can tweak a coffee's flavor development at every point during (and even immediately be- fore and after) the roast: While a spectrometer can help pinpoint some hard data that's useful for record keeping and quality control, those machines don't ever have to actually taste the coffee. "Of course, [it also depends on] the experience and the skill of the roaster. It's more artisan, it's more of a craft," John from Mr. Espresso says. "The guy who does our roasting, Ricardo, has been working with us for over 25 years. He's been roasting for 20 years!" Which brings us, of course, to the next—and arguably the most im- portant—element in the chain reaction that causes green beans to turn brown: the human at the controls. Just loving well-roasted coffee isn't enough to know how to do it, any more than simply enjoying a well-ex- tracted cup of coffee prepares you to make one yourself. For most roast- ers, there is a steep learning curve to mastering the roasting curve: In many companies, roasting expertise and responsibilities are earned through an apprenticeship, which can last as long as two years. When Ian first started roasting coffee for Topeca, the then-much- smaller company didn't have much of an official training procedure in place. "Back then, [it was] just one-on-one working with our head roaster at that time, and mimicking his profiles and doing standard production roasts." Now, he says, new roasters are taught more of the whys and hows of roasting, rather than simply attempting imitation batches. "There isn't a set number of hours [of training], but enough time to have a broad range of experience with beans and roast profiles, and make calls as they see things when they're roasting," he explains. "There are a lot of variables in roasting, so to just throw a roast profile in front of them isn't always the best tactic. We want them to feel comfortable and knowledgeable to make decisions." A roaster also has to be comfortable being alone: Between the heat of the machines, the noise of the drums or the roasting chamber, and the sacks upon sacks of green beans coming in and brown beans going out, roasters tend to spend most of their time standing up and off to the side of the production floor, away from the more social areas of the production, training, or cupping facilities. "It can get very Zen-like, for sure," adds Jon from the Roasterie. As a barista, sometimes stepping inside that zone with a roaster can shed light not only on the process, but also on the product: Coffee is a changeling of an ingredient, and a roaster's job is to try to tame that changeling enough to allow baristas to make the best brews possible. Baristas, however, are the ones who actually interact the most with the fruits of those roasters' labors, since most roasters don't have as much access or opportunity to taste as closely or as comparatively as they'd always like. Ian is a big advocate of bridging the gap between roasters and baristas, and he thinks that "baristas who want to take their craft to the next level, they need to step out from behind the counter if they have the opportunity: Go to the roastery, go to as many cuppings as possible, but especially learn about roasting." He thinks that tasting through roast defects, seeing the process up close, and speaking to the professionals who work the magic in those machines would be a huge boost for a barista's ability to identify the dif- ference between a coffee that tastes off because of a brewing problem, as opposed to immediately blaming the roast. "I would love for a barista to come and actually taste what an underdeveloped roast defect tastes like, or 'roasty' or those sort of different things so that they can actually make that call accurately when they run into those types of issues," he says. "Creating a common language is a task within itself. It starts with the willingness of the barista to want to learn about it." 75 www.baristamagazine.com