What is the roasting process?
Before the roasting process, raw coffee beans are green in color, soft to the touch, and often smell like freshly cut grass. Roasting is the process of applying intense heat to char the green beans, resulting in those brown, crisped, and fragrant beans we know and love.
Essentially, roasting works by drying out the beans, caramelizing the sugars and bringing out the coffee’s, well, coffee flavor in the process. Roasting urges the beans’ captive oils and vapors to the surface and unlocks all of those tasty and aromatic compounds inside the bean’s physiology that make every cup of coffee unique.
The roasting process isn’t strictly formulaic. There’s an art as well as a science to roasting, as we’ll see. And selecting which blend is right for you could vary day to day. It could even depend on how you take your coffee.
For example, a darker roast with cereal or nutty undertones holds up well to cream and sugar, making it an ideal afternoon pick-me-up. A lighter roast, which retains more of its acidity and resembles cane sugar in color—seeing as the beans spend less time in the roaster—can taste citrusy or fruity, like lemon or blueberry.
So here’s everything you need to know about each roast, so you’ll always know which to choose. (Though of course, if you need help deciding, we’re always at the ready with recommendations!)
Light roasts might be the most misunderstood. Because these beans spend less time in the roaster, they take on less of the character of the roasting process. This means that they hold on to more of their origin flavor, a profile that can’t be replicated anywhere else. It’s exclusive to that bean’s particular growing conditions: what part of the world it came from, the nature of the soil, and how much water or shade it got. As far as brewing patterns are concerned, light roasts benefit from drip methods, like pour overs, that filter out fine particles and leave the coffee clean and crystal clear. For this reason, many people like to drink their light roast coffee without any fixings. The beans roast at 350-400 degrees Fahrenheit, which is enough time to turn them golden brown, but not enough time for them to crack. That’s why light roast beans appear whole in shape, but dull in finish; the oils inside haven’t broken through the surface yet.
By the way, in case you were wondering what java to go to when you’re feeling low energy, lighter roasts actually have roughly the same amount of caffeine as darker roasts (though there are urban myths that may tell you otherwise!). If you’re new to lighter roasts, consider trying this African “Horizon” blend: It’s bright and berry-like, almost like liquid candy, with a hint of tang. If you like, we recommend pairing it with something sweet, perhaps a pastry or biscuit.
Known for their balanced profile, medium roast beans are the perfect harmony of acidity and bitterness. Generally speaking, they have a slightly sweeter, mellower flavor and are less intense than a dark roast, but richer than a light roast.
Color-wise, the beans of a medium roast run the gamut from burnt caramel to deep chestnut. The beans are roasted at 400-430 degrees Fahrenheit: long enough for them to take on some of the robust warmth of the roasting process while still holding on to their origin flavor. Said differently, medium roasts can embody the caramelized flavors from the roaster and retain hints of their herby or floral undertones inherited from the beans' home soil.
“Medium roast” is a shorthand for a very significant spectrum of coffee. In fact, every roaster has their own guidelines for deciding what makes a medium roast “medium,” and what tips it over to the light or dark categories. Some specialists even denote a fourth roast, medium-dark, which is to say that this is a vast category with infinite possibilities.
If you’ve enjoyed a cup of coffee at Compass but aren’t sure what roast you tried, chances are it was a medium roast. Our go-to favorite is our Cardinal Blend, our original roast, known for its even, nutty, and caramel taste. The beans, which are sourced in Central America, maintain winks of their origin flavor, resulting in Cardinal’s signature milk chocolate profile. This compliments the toastiness adopted from the roaster. And finally, also thanks to the roasting process that unlocks all those yummy oils, medium roasts like Cardinal have a more velvety mouthfeel than a light roast. (In case you were curious, “mouthfeel” simply refers to the texture and sensation of the coffee when drunk!)
At this point in the roasting process, the beans themselves appear practically onyx in color. As previously mentioned, dark roasts spend the most time in the roaster, which means they take on the most character from the roasting process, leaving the beans waxy and cracked, gushing with the flavor and aroma from the beans’ activated oils. Which, you guessed it, leads to a richer mouthfeel. The preferred brewing methods for dark roasts are the ones that allow the coffee to put its creamier texture on full display. So go for a course filtration, like a French Press, to highlight the coffee’s natural sediments and satiny feel.
Dark roasts are the inverse of light beans, which means they’re less acidic and more intense, resulting in nuttier and smokier blends. They’re also full-bodied and robust in flavor, strong enough to hold up to any carnival of cream, sugar, or flavorings you so desire.
Dark roasts can vary immensely from blend to blend and taste anywhere from earthy to nutty to fruity, so be sure to keep experimenting with different origins and roasting styles (lucky you!). If you’re interested in seeing the difference for yourself, try this tasting trio: start with an introductory dark roast, like this brown sugary Waypoint blend. Then, for a smokier undertone, go for a steaming mug of Azimuth, known to be warm, earthy, and intense. And finally, if you’re fancying a fruity afternoon treat, pour a cup of Shaw with cream (or cream alternative) and sugar. It’s lush and juicy, with bursts of cacao and stone fruit.
A Final Note
Of course, this is an art and a science. The bean will take on and unleash different flavor profiles thanks to a litany of factors, including the grinder, processing method, age, and brewing style, not to mention where and how it was grown. This is just a guide. There are no universal regulations or standards for roasting coffees, so the results vary from roaster to roaster.
Which is to say that you’ll have to keep exploring. Ask questions. Trust your intuition. And savor the journey of discovery.