Roasting adds layers. Much like your Sunday roast cut of meat or a tray of root vegetables for a mid-week dinner, when you roast them at high temperatures different flavours emerge and elevate the everyday into the extraordinary. Coffee is much the same, and the degree to which beans are roasted is one of the most important factors determining flavour, hence why different coffee roast levels exist.
To give a bit of background, in case you wondered, the pre-roasting ‘green’ coffee beans are soft with an almost herbal, earthy or grassy scent with little to no flavour. With the combination of heat and time, these raw beans are transformed into little crunchy, aromatic morsels. Roasting transforms the ordinary fruit of the coffee plant into something radically good.
Of course, other factors affect the final taste – like origin. We personally choose to source Arabica beans in a FairChain agreement with farmers in Ethiopia (check out our impact page for more!), exclusively because we’re passionate about trading fairly and helping ensure farmers aren’t screwed by the big corporate coffee system. But beans from, say, Guatemala and beans from Indonesia will taste very different, even if roasted to the same stage, so it does pay off to be discerning about where your beans come from.
Now, there are different coffee roast levels which result in a variety of pretty standardised flavour profiles. It’s pretty self-explanatory that the longer a coffee bean is subjected to heat, the darker its colour becomes, this is due to oils appearing on the skin during the process. So, fittingly, the most common way to differentiate your roasted beans is by colour, from light to dark. Without further ado, here is your detailed guide to the different Coffee Roast Levels.
Light roasts have a toasted grain taste and strong acidity. Light brown in colour and generally heated to only around 200ºC, at this stage the beans have a ‘first crack’ and expand in size but don’t go beyond that. This captures those innate flavours (and the bulk of the caffeine) that will be far clearer in the final taste than any other roast.
Blossoming into serious body territory, medium roast beans exhibit a more balanced, open flavour and a desirable aroma and acidity to suit many palates. Most ‘Breakfast Blend’ marketed coffee is medium roasted for maximum appeal. Medium brown in colour, these beans are brought beyond first crack stage but never quite reach second crack, so they stop at around 220ºC. A good all-rounder, though the caffeine levels are decreased slightly.
At this stage, beyond the second crack, oils have begun to appear on the surface of the beans as the internal temperature is amped up to around 225/230ºC. The roasting process has not only given a darker, richer brown colour, but it’s also left more of a mark on the flavour of the bean. Nutty, spicy, toasted notes abound.
Dark chocolate in colour and just as rich as its cocoa counterpart, dark roasts are velvety rich and incredibly full-bodied. However, the flavours are not so much the intrinsic coffee bean flavours they begun with but eclipsed by more of the roasting process than anything else. Heated to just below 250ºC, this is the end of the second crack stage and the farthest roasters will take a bean. After this, a burnt taste can come through with back flavours of tar and charcoal. Not particularly nice in a restorative, energy-giving cup of coffee. Here, the caffeine levels are at their lowest and it’s an oilier brew, as each bean has a light sheen of oil on the surface. This is bonfire bold, heavy on the toasted scale with a possible hint of smoke but a luxurious creaminess.
If you’re not too bothered by the technical stuff (or if you’ve skipped through this article to get to the conclusion – we’ve been guilty on other blogs ourselves!) basically it’s this: as coffee roast levels gets darker it tends to lose the bean’s original, unique flavours, taking on more taste characteristics of the roasting process. Lighter roasts have more acidity, clearer distinctions and a sharper, drier taste whilst darker roasts have more of a heavier, creamier taste with less acidity but significantly less caffeine.
At the end of the day, it all comes down to taste. Your personal preference. You might prefer a lighter, more intense flavoured coffee to set up for a morning replying to emails, or you might prefer the darker, robust roast for the mid-afternoon slump to see you through to home time. Your coffee preferences are as individual as you are and dependent on mood, time of day and a host of other factors – so it pays off to know the difference in coffee roast levels.