In last installment of the beginner's guide to coffee, we gave you some background on the processes that take your coffee from seed to valuable export. Now it's time to take those beans and make them into a strong cup. For continuity's sake, this guide will pick up where the last one left off, roasting.
Roasting is a highly-skilled process which has seen a huge transformation and evolution with the renaissance of small-batch roasting. At its heart, roasting is a chemical process, using heat to gently caramelize the sugars within the coffee beans and bring out flavors. The key to the perfect flavors lies in finding a roast which can highlight the flavor profile of the coffee's given region, offering a plethora of tasting notes, while keeping it light enough to avoid the release of too many tannins (which contribute to acidity). Ideally speaking, each bean or blend should be roasted differently allowing for seasonal changes in roasts. Some roasting characteristics from light to dark include:
- Cinnamon Roast: at this stage, the beans are still very light in color, they look somewhat like peanuts. Flavors: The level of acidity is rather high at this point, with grassy flavors and a graininess similar to the malt used in dark beers.
- Light Roast: The beans will have a darker caramel color, Flavors: This is a preferred roast for artisan roasters wishing to highlight a single origin bean. This roast features a complex acidity, like a Cabernet Sauvignon, fruity flavors shine through in the profile.
- Medium Roast: this roast is sometimes referred to as first pop, as the beans will make a popping sound during the roasting process. This is the most utilitarian roast, as it complements the flavor profiles of a large variety of origins. Flavors: Muted acidity, roasty sweetness, notes of chocolate on the nose, with a velvety breadth and a sweet finish, imparting some of the characteristics of the roast.
- Dark Roast: The dark roast generally occurs at the second pop of the beans; the beans are a dark black. At this point in the roasting process, the flavor of the bean will be more dominated by its roast, rather than its origin. Flavors: Acid is neutralized at this state, bittersweet, with notes of caramel on the nose, and a full, roasty flavor imparted from the roasting process.
- French/Italian Roast: The blackest of the black, at this point the finished bean will be quite oily to the touch. Flavors: A burnt flavor characterizes this roast, with a low level acidity, the flavor profile is somewhat muted, allowing the roasting process to speak for the bean.
After the roasting process has gotten the bean to its desired flavor profile, care must be taken to impart the flavors of the bean into water, this is where extraction occurs. The extraction process begins by turning the hard beans into a more usable, ground form. Grinding can be done with a burr grinder (preferred) which uses the pressure of abrasive gears to pulverize the beans, leaving their oils intact, as no heat is used in the process. Beans are more commonly chopped with a blade grinder, which is capable of grinding the beans at high speed, however it cannot grind the beans as uniformly and must be cleaned thoroughly to eradicate coffee dust from previous grinds.
Water is then added to the grounds to finalize the extraction process. Chemicals and equations aside, the beans are water soluble, so think of your coffee as the finalized solution of beans and H20.This process imparts flavors and ideally highlights the flavors sought out in the roast. Extractions can be as short as a couple minutes (espresso, pour over), Hours (cold brew), even days (Kyoto), and are suited to the grind size and final output. Stay tuned for PT. 3 when we explore how this extraction can be used.