How Coffee Is Roasted Part 2: Deciding On A Roast Level

In "How Coffee Is Roasted Part 1: The Roasting Process" we learned about what changes coffee beans go through during a roast and how a roaster uses certain parameters to decide how to roast a coffee.  In today's blog post, we are going to learn how roasters decide how light or dark a coffee will be roasted.  We will learn about flavors from different coffee regions as well as how processing methods influence a coffee roaster in deciding on a roast level. If you didn't geek out enough with me in part 1, then you might get your fill after part 2, so buckle up!

The first thing we are going to focus on is coffee growing regions and inherent coffee bean flavors.  There are 3 main growing regions, and those are The Americas, Africa, and Asia Pacific, and all those regions are within the coffee belt as shown in the image below.


Coffees from The Americas are grown almost everywhere in the American continent, except for the United States, Canada, the Caribbean Islands, and a few countries in South America.  Coffees from The Americas largely boast flavors of cocoa, nuts, and malic fruits (apples, peaches, and grapes).  Because of their flavors, American coffees taste best if they are roasted closer to medium rather than light, as that brings out and sweetens the cocoa and nutty notes, and in my opinion makes for a wonderful drinking experience.  In my experience, most American coffees don't taste as well as they could when roasted light, as they tend to be fairly acidic and not very nuanced.  However, Colombian coffees are an exception in that they taste wonderful when roasted light, medium, or dark.
African coffees are sought after for their rich, complex, and sweet fruity and floral notes, and they are very popular in the current coffee culture.  Because of their flavor complexity, most African coffees taste best when roasted light to medium light; any darker than that the coffees will lose a lot of their wonderful fruity flavors, and more chocolate notes become prominent.  Kenyan coffees, much like Colombian coffees, are an exception in which they actually taste better when roasted closer to medium and even dark because of their very high acidity and savory vegetable flavor notes.
Coffees from the Asia Pacific region are known for their prominent flavor notes of spices (clove, cinnamon, pepper) herbs (cardamom, rosemary, fennel), milk chocolate, cedar, and malic fruits.  When roasted light, the flavors and the acidity of Asian coffees can be almost overwhelming and a bit off putting to a lot of coffee drinkers, which is why generally Asian coffees are roasted to medium and a lot of times to dark.  When roasted medium to dark, their acidity sweetens, the milk chocolate flavors become more prominent, and the spice notes mellow out, thus creating a much more balanced cup of coffee.

 Now that we have a better understanding about how the flavors from coffees from different regions vary, I'm going to briefly explain how coffee processing methods affect how a coffee roasts as well as its flavors.  The four main coffee processing methods are washedwet hullednatural, and honey.  I won't go into much detail regarding the different kinds of processing methods in this post (that will be on a different blog post, so stay tuned!), but I will categorize the four methods mentioned as "little sediment" and "a lot of sediment".
"Little sediment" coffees, which are washed process or wet hull process, are denser and cleaner of sediment, as the category suggests, and these coffees can be delicious at almost any roast level that you can imagine...well, except maybe a roast so dark that the beans turn into literal charcoal, but you get the point.  In general, "little sediment" coffees are more versatile when it comes to roast level because they are more dense and can have much less roasty or burnt flavors when roasted dark because of how little sediment they have.  The photo below, which is the Colombia that goes into KLLR's "The Americas", shows how little to no sediment, aside from maybe some chaff, is left on the bucket.


"A lot of sediment" coffees, which are natural process and honey process, are less dense, a bit more porous, and contain much more sediment than washed coffees.  This sediment is a derivative of coffee cherries, and it is also much more prone to burning than the green bean itself, which is why in general "a lot of sediment" coffees taste best when roasted light.  Of course these types of coffees can also be roasted dark and taste delicious, like Brazilian coffees, but it all also depends on the inherent bean flavors and what flavors a roaster wants to achieve.  We roasters also have to be careful not to roast too light, otherwise "a lot of sediment" coffees will have an acidity similar to vinegar...The photo below, which is the natural process Ethiopia that goes into KLLR's "Natural Africa", shows some sediment left in the bucket; as the coffee sits and is shifted around in the bucket, more sediment will be left behind.

 Of course every roaster has the right to roast their coffees in whatever way they feel is best, there is not one correct way to roast coffee.  One other thing that roasters have to consider in deciding how to roast a coffee is their client and customer base, as some roasters have more clients that like light coffees and others have more clients that like dark coffees, and that's okay and it is good for the coffee industry.  We roast our coffees the way we do at KLLR because that's what our customers and clients like, and it is how we believe we should be roasting our coffees. Of course as our customer and client base changes, we will make the necessary changes in order to continue being a better coffee company because we believe everyone deserves good coffee.