What is First Crack?
Coffee people sometimes talk about the “first crack,” which is a sound that occurs at a key stage in the coffee roasting process. You may hear this in context when a coffee roaster announces, “We only roast until the first crack,” or, if you’re standing right next to the roasting machine itself, “Now listen for the first crack!” It sure sounds invigorating, doesn’t it?
The first crack is actually a “crack” sound that roasters utilize as a cue to not only figure out where the roast is in the timeline, but also what to do next. It’s an audible milestone that lets you know where your coffee beans are from green (unroasted) to brown (ready to brew). The first crack is literally the sound of the coffee bean transforming through a process where it takes in heat internally (from the heat of the roaster), converts its internal moisture into steam, and starts releasing heat externally—it’s a process.
When does the first crack appear?
The first crack occurs at a bean temperature of around 380°F, give or take. When the first crack is about to occur, the smoker may want to tone down the heat of the roast, and after the first crack, some smokers may stop smoking altogether. Depending on what flavor profile is desired, it is vital to know when the first crack occurs so that you can take the next steps.
So the first crack was literally an audible sound that I could hear?
Yes.
How does it sound? Is it always the same?
When the first crack occurs – and exactly how – depends both on the characteristics of the coffee being roasted and on how the roaster applies heat. To learn more, Sprudge turned to an experienced coffee roaster, a quality assessment specialist Coffee Quality Institutefounder Wrecking Ball Coffee Roasterscreator of the term “Third Wave Coffee“and generally to Sprudge’s friend Trish Rothgeb, for some clarification:
“With some coffees, you can barely hear it,” Rothgeb says, explaining that some beans sound very gentle — “and you can barely hear them at all” — while others will sound “very popping, like you’re popping a bubble wrap or something.
When the first cracking occurs will depend on how heat is transferred, whether the beans were heated faster and hotter, etc., Rothgeb explains. “There can be a long and loose crack, which means it takes a long time and is kind of disconnected. This might be okay. In most cases, if it is a really quick and uniform crack, it may mean that you have accelerated too quickly at this early stage.”
What happens after the first crack?
Once the first crack is reached, the coffee bean will continue to heat up, this time pressurizing the internal gases (primarily CO2) in the bean. When the pressure of these gases becomes too much for the bean structure, the roaster will hear a second crack. Some roasters who prefer to offer a lighter roast style will stop the roast before the second crack occurs. After the first and second cracks, there are no further cracks—the coffee simply becomes darker and more roasted over time.
Does coffee give any signals that the first crack is about to occur?
“Just before the first crack, you can smell the Trier and feel it change from toasted bread to caramelized,” Rothgeb says. “You can feel that tipping point from grainy and gritty to coffee,” he adds. “Only roasteries can smell that. It’s a really handsome scent. It’s a handsome thing to experience.”
At that point, Rothgeb says, “the bean has stopped having energy fed into it and now it’s so hot and expanded and sizzling that it then pushes out the energy in the form of heat waves, so it becomes exothermic — and that’s when you’re close to bursting.
Is it still fashionable among coffee roasters to say that they “burn only until the first crack”?
While there was certainly a point in time when it was fashionable for a roaster to announce that it was “only roasted to the first crack,” Rothgeb feels the heat of that moment in coffee has passed.
“I think we’re seeing modern roasters have different roast levels on their menu and feel good about it,” he says. “The first crack will always happen – it always SHOULD happen – people should burn at least until the first crack.” He explains the process like blowing up a balloon:
“When you blow up a balloon and it’s really tight and you have to put a lot of pressure into it, and suddenly the balloon expands, that’s it [like] first burst. And when you inflate it, it’s easier to inflate it – and then the second burst would be close to bursting the balloon. So they’re two different things and all the heat and pressure is released in the second burst. The first burst is about the expansion of the cells, which just has to happen [the availability of soluble solids] “or you leave too much flavor on the table,” Rothgeb says.
Nowadays, as coffee lovers, we can be ecstatic to find roasters who embrace both delicate and medium roasts, and more importantly, roasts tailored to bring out the best aroma, flavor, body and acidity from a given coffee. But whether your favorite roast style is just after the first crack or progresses to a mellow medium or darker roast, whoever is in charge of the flame will need to know when the first crack occurs in order to make the most of each little bean’s journey.
