Around the roastery: a basic overview of how the magic happens
Over our short few years, a lot of people have expressed interest in learning about coffee roasting. We’d like to share a little bit about what the roasting process is like, how we choose the coffees we add to our lineup, and the people behind our operation. And, of course, part of roasting is talking about sourcing coffee, as different coffees have vastly different inherent qualities.
Our Director of Coffee, Rob Maynard does the majority of the actual coffee roasting, as well as spearheads our process of selecting which coffees to bring into our product line. Rob has over 10 years of experience as a production roaster, which includes extensive quality control experience.
Pictured: Rob Maynard unloading coffee from the roaster's cooling tray. Photo by Jacquelyn Potter
When we receive coffee, it comes in large burlap bags stacked and wrapped up on top on a pallet behind our store. We check the coffee in, then start moving the bags over to our roastery where we will store it until it’s time to roast.
The unroasted, or “green”, coffee must be received dry and stored quickly. Part of our health and safety practices for the roastery includes being trained to taste and visually inspect green coffee for different defects, including damage to the coffee on a farm level or during transport. The coffees we choose to buy are defect-free and all score over 80 points when evaluated by a professional Q grader (basically a coffee sommelier) .
We look at a lot of factors when we buy new coffees. Some of the coffees in our lineup are pretty much always there (Vietnam Opal Bold & Costa Rica La Minita, to name a couple), while others rotate through. Our core coffees have been reliable crops year-to-year and crop-to-crop and we view them as important pillars of our program. Sometimes we like to mix up our offerings, adding coffees that importers or farmers send us samples of that really wow us on the cupping table, or we may be looking for a specific origin/quality to highlight.
The Actual Roasting
When we start our production roasting days, we weigh out each batch of coffee during cafe hours. Once cafe hours are over, we turn on the roaster, as well as the thermal afterburner. The afterburner incinerates the emissions before they hit the atmosphere. It’s very loud during operation, so that’s why we don’t roast coffee during shop hours. Once both of these machines get up to temp, we will drop the first batch of green coffee into the drum of the roaster. During this time, Rob and our production assistant will be monitoring a graph of the temperature of a probe, which sits inside the drum of the roaster where the coffee beans pile up as the drum turns. As the roasting continues, they will change how much gas the roaster’s burners are getting in order to control how fast the temperature of the bean probe changes.
During roasting, coffee goes through a few important changes. Often times, roasteries (ourselves included) will refer to these in phases. First, the drying phase. This is when the coffee is losing moisture due to the addition of heat. Then, sugar browning (or maillard). During this phase, there’s a chemical reaction as the sugars in the coffee caramelize and develop. This phase is crucial, as with most coffees we are looking for them to have a sweet finish. It also smells like fresh bread baking, so that’s a bonus. Finally, after letting out a faint “crack” sound, the development time phase begins. This period is where you’ll start to taste the actual roast of the coffee.
As roasters, we are looking at both how quickly changes in temperature occur in the coffee, as well as what the temperature is. Understanding the different phases of roasting, as well as how to control them is essential to produce an excellent roast of coffee. Our job as roasters is to enhance the inherent qualities of the coffee and bring out the most pleasant taste experience possible. Developing the sugars, bringing out the complexities in the coffee, and choosing how much to develop the roast of the coffee, are all going to have an impact on the final cup.
There’s a common misconception that most of the flavor profile of a coffee comes from the roasting process, but actually roasting is meant to bring out the qualities that the coffee already possesses. Roasting can detract from or enhance those qualities. Different conditions at the farm level are where the base of the flavor profile comes from. These conditions include, climate, altitude, coffee plant variety & species, as well as how the coffee is picked and processed.
The coffee supply stream is extremely complex and it takes great effort, often across multiple continents, to produce the coffee that many of us rely on daily.