What’s in a roast? A whole lot actually. Roasting is a crucial step in the long journey that takes a humble bean from a tree to your cup. How coffee is roasted plays a major role in aroma, flavor, and body.
First let’s dispel a couple of common misconceptions.
Dark roasted coffee does not have more caffeine than light roast. It’s actually the other way around. The reason that dark roasted coffee has less caffeine is that it loses caffeine through steam and smoke in the roasting process. The longer the coffee roasts the more of that caffeine evaporates.
Light roasted does not mean light in flavor, some light roasts have such a powerful brightness that they seem to almost attacks your taste buds. Every coffee bean contains a certain amount of acids and sugars. The amount that they start with depends on how it was grown. Rainfall, soil content, shade or full sun grown, the list goes on. But the amount of sugars and acids that end up in your coffee pot is dependent on the roasting process. It is a delicate balance of power that the roastmaster tries to control. The lighter roasts tend to have that balance shifted in favor of acidity, which we call brightness in the trade. Darker roasts allow more sugars to cook and end up having a sweeter taste.
Go out and try a few for yourself. Just remember, freshness matters. If the coffee is any more than a couple of weeks old, you won’t be able to pick up on any of those nuances we just talked about.