Guatemalan coffee has been my favorite origin for a few years now. The rich body, sweet cocoa flavors and that deep, almost fruity sweetness are just the thing I need right after rolling out of bed in the morning, and the balanced acidity helps to perk me up. I give a lot of credit to Pangea Coffee Roasters for helping me develop my love of Guatemalan coffee.
Being my favorite origin and also the one I have the most experience roasting as a hobby roaster, I knew that Chipset's first production roast had to be Guatemalan. I selected a USDA certified organic coffee out of Huehuetenango, a region in Guatemala known for producing high quality specialty arabica coffees. The flavor profile of this coffee is citrus, honeycomb, almond butter, and milk chocolate, and my job as a roaster is to coax as much of that out as possible while delivering a delicious cup of coffee.
Coffee selected. Next up, the roaster. I use a drum roaster that can roast batches of around 2lbs at a time. A cylindrical drum tumbles the beans continuously so they roast evenly without burning, a heat source pushes the drum past 400°F, and a fan moves air through the beans to manage convective heating, smoke, and moisture as the roast progresses.
During the roast, coffee beans go through three phases. First, the drying phase drives out moisture from the raw bean. It turns yellow and produces a grassy, almost hay like aroma. Next comes the Maillard phase, where natural sugars begin to caramelize and the bean develops nutty, toasty, caramel, and chocolate flavors. Finally, development is where those Maillard flavors deepen and body and sweetness peak. But it's a balancing act; spend too long here and the roasty, smoky character of a dark roast starts to overpower the bean's origin characteristics (in this case, the citrus, honeycomb, almond butter, and milk chocolate notes I was working hard to preserve).
A roaster's job is to balance the time spent in each phase by manipulating heat and airflow throughout the roast. That means deciding how much coffee to load, how hot the drum is when the beans go in (charge temp), what temperature to stop roasting the beans at (drop temp), and precisely when to dial heat and airflow up or down. Every adjustment influences the bean temperature curve, and that curve is what determines the flavor in your cup.
Here's what that looks like in practice. Each line represents a variable I'm controlling in real time to guide the beans through those three phases.
Batches A-E explored how this bean accepts heat; F-L focused on balancing development phases and dialing in charge/drop temperatures (with F suffering a technical error that tanked the heat mid-roast and threw the phases off); M-P fine-tuned the flavor profile, balancing fruitiness and chocolate.
After roasting, I use a standardized tasting method called coffee cupping to analyze what ended up in the cup. The process is simple: coarsely ground coffee is steeped in hot water, and after a few minutes you break the crust of grounds and start tasting. It strips away all the variables of brewing equipment and technique, so you're evaluating the roast itself.
For this coffee, I was chasing a cup that honored the bean's natural flavor profile: brightness up front, sweetness in the middle, and a clean chocolate finish. Some early batches were too light; the acidity was sharp and the sweetness hadn't fully developed. Others were pushed too far, and the delicate citrus and honeycomb notes got lost. The roast that finally clicked had a development time that let the Maillard flavors fully integrate without sacrificing the origin character that makes this bean special.
That's the roast that became Chipset's first product. If it sounds tasty to you, you can buy some here - https://chipsetcoffee.com/products/guatemala-medium-roast.
Want to geek out further?
Coffee Roasting Software
We use Artisan, an application for roasting coffees, for all coffee roasting at Chipset. The images from the gif are screenshots from Artisan. Aside from having a huge community of coffee roasters to talk to, the coolest thing about it is that it is free and open source. As long as you have a compatible roaster, you can start using it today at no cost. Check out Artisan on GitHub.
Chipset is not affiliated with Artisan in any way. We just love it!
More on Coffee Cupping
Who doesn't like some James Hoffman content? Check out James' video on cupping coffees here.