Perfect storm — matching brewing methods and coffee roasts
The dark and light sides of coffee
Although the coffee industry has no single, universally accepted standard for roast levels, we can distinguish three basic roast profiles: light, medium and dark.
Generally, light roasting at lower temperatures preserves more aromas linked to the bean's own character. A light-roasted coffee therefore immediately reveals citrus and floral notes: the very ones the seed absorbed while ripening on the plantation. By comparison, medium roasting brings out sweeter smells and flavours; chocolate and caramel are our favourites. And a dark roast? That is for lovers of coffee's truly dark side. Every sip delivers the characteristic bitterness associated with the pain of getting up for work...
That covers what roasting can contribute to flavour. But to experience the wealth of aromas planned by the roaster, we still have to brew the coffee. This stage can help or, unfortunately, harm it, depending on whether we choose the right or wrong extraction method — in plain language, the brewing method.
Extraction is a physicochemical process in which a solvent helps release substances responsible for specific flavours from a roasted bean. In coffee brewing, the solvent is that mysterious compound dihydrogen monoxide — in other words, water. Water releases successive flavour and aroma notes carried by substances such as sugars, fats, acids and alkaloids, those extremely important compounds associated with caffeine. What is the problem? Each group of compounds is released — or, more precisely, breaks down — at a different time. Compounds responsible for citrus and floral notes emerge first, followed by sugars associated with chocolate and caramel, and finally substances carrying bitter flavours. What does this have to do with brewing? Just about everything.
Pressure or a gentle drip?
Coffee brewing methods can be divided roughly into pour-over and pressure-based methods. We will discuss their advantages and disadvantages separately, so here we will focus on the main difference: how they affect what ends up steaming in our cups, in relation to the profile devised by our talented roaster. Pour-over methods, such as the drippers and Chemex brewers that have become popular in recent years, work slowly. Coffee passes through a special filter into a vessel, drop by drop. They are therefore best suited to light-roasted beans, which are less porous, meaning their compounds need more time to be released. This gives the beans time to show the full complexity of their flavour bouquet.
Pressure-based methods, including professional espresso machines, classic moka pots and alternative AeroPress brewers, speed up brewing, sometimes producing a finished drink in a matter of seconds. Pressure extraction is intense, so medium- or even dark-roasted beans work best. Why? These roasts produce a characteristic bitter flavour. To preserve it while retaining a wonderfully full body, you need to work quickly, hence the energetic pressure methods that deliver a brew almost immediately. Voilà!
If you have reached the end without already rushing off to compare a little black coffee from a modern AeroPress with one from an elegant dripper, we encourage you to do just that. Experiment, taste and find the best way to create your perfect morning cup!
