A Look At How The Coffee Roasting Process Affects Bean Flavor
Open up a bag of whole bean coffee from your local supermarket and you may not be surprised to find it full of shiny dark brown beans.
For many of us opening the bag constitutes the peak of the coffee experience, with a quick trip downhill thereafter. Often, what ends up in the cup doesn’t live up to the delicious promises that the bag seemed to offer.
Roast level influences the taste of coffee so much so that it can make or break your coffee drinking experience. The vast majority of whole bean coffee sold by chain grocers is the product of huge roasters that literally bake all of the flavors out of the bean.
If you look in the right places, however, you may begin to find bags of whole bean coffee caringly roasted at just the right level. Most small or specialty roasters offer a variety of beans from different coffee growing regions all over the world, roasted at the level that best brings out inherent flavor qualities of the bean.
Most coffee growing regions throughout the world produce beans with a distinct flavor profile that can either be enhanced or destroyed by the roasting process. Drinking a cup of coffee made from high-quality beans that’s not a product of the typical over-roasted lot, may open the door for many of us to a world of inspiring coffee drinking experiences.
So why does roast matter? For one, coffee beans undergo a chemical change when exposed to heat. The higher the temperature, the more natural sugars are brought out from the bean. Roast beans too lightly and not enough of the sugars will transform, resulting in coffee that tastes grassy and sour. Roast too darkly, (most supermarket coffee), and your beans will taste like barbequed carbon.
So why would large roasters over roast their coffee? Why wouldn’t they just roast at the perfect level to achieve coffee drinking bliss?
Beans prepared for a mass market are beans that are grown in huge lots or a combination of countless small lots, and often have poor flavor profiles due to inconsistency in cultivation. Most of the time these beans are harvested in cherry form with other coffee cherries that are under-ripe, too ripe, or rotten. So, mass roasters over roast their coffee to hide all of the imperfections in the raw bean.
Why should roast matter to you? Well, if you’re just drinking coffee for the caffeine, then it shouldn’t matter, frankly. But for those of you who really enjoy the flavor of coffee and want to see what more there is to offer, then the roast absolutely matters.
Let’s return to that bag of whole bean coffee at the beginning of this article. Let’s open it again; but this time, we find that it’s a bag of single origin, small batch beans prepared a local roaster. The label indicates they are medium-light roast beans from Ethiopia.
Instead of the smooth, glossy, dark brown beans we typically see, the beans in this bag are smaller, much lighter in color, barely moist looking, and slightly bumpy. Tiny ridges on the surface of the bean are visible, and the crack running down the center will be more pronounced than the typical over-roasted bean.
The coffee beans in this bag have been roasted at just the right level to accentuate the natural flavors of the bean, without taking it too far. How did the roaster know just how far to take the roast? Choosing a roast level is dependent on the bean origin, roaster preference, and plain old experience acquired by trial and error.
Coffee in its raw form starts out as small, hard, green seeds (or beans) inside the cherries of a coffee shrub. Once the coffee cherries are harvested and the beans are removed and dried, they’re ready for roasting. Most beans are roasted in a drum roaster, which constantly tumbles the beans around, constantly exposing the beans to hot air.
The beans slowly begin to expand as the temperature inside the drum increases. As the beans heat up further, they darken and their chemical structure begins to change.
Depending on the hardness and size of the bean, the real changes in flavor begin to take place +/- 400℉, when they start to make sounds similar to popcorn popping. This is called the first crack. From this point on, a roaster can stop the roast at any time and produce a drinkable cup of coffee.
Keep the beans in the heat long enough, and 15 to 20 degrees later, the beans will have become even darker in color. They will also have expanded quite a bit and experienced a second crack, which is similar to the sound of toothpicks snapping.
At this point, the beans will have entered dark roast territory where the taste of the roast starts to overtake the natural taste of the bean. Anything beyond this level is most likely what you’ll find in a bag of beans produced by most mass roasters.
So, if you’re in the mood to explore what the natural flavor of coffee has to offer, look for bags of the whole bean offered by small or specialty roasters, or at the very least, bags labeled “light” or “medium” roast. You may be able to find a bag or two at a commercial grocery chain. You can be sure to find some at specialty markets. And, your surest bet will be to purchase some beans directly from a specialty roaster either online or at their shop.
Once you get your hands on some, brew up a cup. It should become clear you’re no longer drinking coffee with that same old caramelized toasty taste you’re used to finding in every other cup. You won’t need to drown this coffee in cream and sugar.
Instead, you may notice behind the earthiness and sweet hint of caramelization there are strong waves of mild fruit flavors such as blueberry, or slightly floral accents such as rose, or deep rich tones of fig or plum in the cup.
And with each new bag of the whole bean that you buy from all over the world, roasted at different levels, you may get to enjoy a whole new coffee drinking experience thanks to what’s in your roast.