What Does Roasting Do To Coffee?
You’ve got to wonder how we figured out coffee. Because you wouldn’t know there was anything special about it by looking at green beans. They’re mostly unremarkable, taste and smell like wet grass and dirt, and don’t start out with as much as a hint of their potential.
Without roasting, coffee doesn't have any trace of the flavor and character that we enjoy.
Roasting is like finding the password to coffee’s flavor and personality. Most of the time, it’s not a gimme. The potential is coded into every bean, but there are countless sequences that can be tried and only a few that work.
Covering the journey from light roast to dark, here’s how roasting nudges coffee out of its shell.
First crack and distilled origin flavors
The roasting process is punctuated by two audible “cracks.” These two cracks are important benchmarks for roasters. At around 370°F, we get the first crack and the coffee is considered to be lightly roasted. The beans appear dry and just a shade past tan.
Light roasting is kind of like a game of chicken, where the idea is to get the coffee as close as possible to a certain point before getting it out of the way.
The goal is to capture flavors that may only be present for mere seconds. Some of these flavor combinations may only emerge once before they’re gone.
Light roasts are adventure coffee. Because taste is determined by region, instead of by roast, you never quite know what you’re going to get.
So what do light roasts taste like?
When done right, a light roast distills the extreme characteristics that make a coffee unique. The coffee from Colombia often tastes nothing like coffee from Sumatra, and even beans from one farm may share little in common with those of a neighbor.
Light roasts are best for capturing and highlighting those distinctions.
As a result, the taste of light roasts can range from cherry or blueberry, to chocolate and bourbon, or orange peel and spice - or like none of those at all. With an unending variety of flavor, light roasts might not always be a fan favorite but they’re always interesting.
Arriving at The American Roast
At around 400°F the coffee browns beyond its early cinnamon tone and takes on a thin coat of the familiar roasted “coffee” flavor. The second crack has still not happened. Most people call this point the medium or “city roast.” In a lot of cases, a medium roast can still be pretty light. Maybe even lighter than some light roasts.
What makes a medium roast?
As with most things medium, medium roasts tend to satisfy tastes on both sides of the spectrum. There’s enough origin flavor for the light roast drinkers and enough of a roasty note for those who like darker coffee.
Though not the defining trait of medium roasts, caramelization throws its hat into the ring at about this point.
Coffee beans contain natural sugars that, when roasted, heat up to add a satisfying note of crispiness to the flavor. The combination of residual origin flavors, a potent natural acidity plus the glowing sugars inside can easily lead some mediums to be just as one-of-a-kind and unpredictable as any light roast.
Things are getting dark. The second crack of the roasting process lets you know that the sun is starting to set.
French roasts. Italian roasts. Vienna roast. Originally a distinctly European custom, the dark roast family was perfected overseas before being adopted in the US.
Pushed heavily through major coffee chains, gas stations and convenience stores, if we had to guess, dark roasts are probably the most popular roasts in the country.
Unlike light and medium roasts, dark roasts take the coffee out of the equation. There are few origin flavors to speak of at this point in the roasting process.
Defining dark roasts
Darker roasts are characterized by an oily shimmer and a “bold” flavor of fully caramelized sugars bordering closely on burnt. Some call dark roasts smoky, intense and robust.
Dark roasting is typically the most consistent method for getting coffee to a drinkable point. A lot of specialty roasters may not let their coffee get dark.
That’s because their flavor depends much less on the original characteristics of the unique strain and instead relies on the uniform taste of cooked coffee.
What’s Your Roast?
Coffee is naturally uncooperative. Getting any level of roast to complement coffee the way we like takes time to fine-tune. Only after we figure out how to cajole the dormant oils and sugars will we get something new and interesting, or something comforting and recognizable.
Whether you like your coffee with one crack or two, there aren’t many drinks out there quite like coffee.