Cupping is the industry term used for the process of analyzing a coffee based on its sensory qualities - for example, its aromas and flavors. For our cuppings at Equal Exchange, roasted samples of coffee are divided into six different glasses of equal amount and grind size, steeped with hot water (198 to 205 degrees), and slurped (or aspirated) from a spoon for about 35 minutes.
Aspiration is the process of slurping a beverage across the tongue with force, in a way that introduces air into the mouth and sprays the beverage across all parts of the tongue rapidly. If you've ever heard or seen a wine expert doing a tasting, this is the same method they use. Aspiration also forces the coffee's aromatics up from the back of the throat to the olfactory bulb (a part of our brain that sits behind our eyes and is responsible for processing scent). Everything we taste is affected by its aromatics, making flavor and aroma intrinsically linked. Each coffee is graded based on the quality of their aroma, flavor, mouthfeel, acidity, balance, cleanliness and aftertaste.
The olfactory bulb is the part of our brain that processes scent. Aromas reach the nerves of the olfactory bulb via two routes: 1) through the nose, nasally, and 2) through aromas rising up to the bulb from the back of the throat, what we refer to as retronasally.
In cupping, we analyze aromas in three different stages.
- The dry stage: when we smell the dry, ground, roasted coffee in the cup.
- The crust stage: when we smell the "cap," of the coffee as it is steeping.
- The break: when we break the cap after four minutes of steeping and smell the release of the aromatics that were trapped underneath the cap.
It may be surprising to find out that there are only five basic flavors: sweet, sour, salt, bitter, and umami. You've probably heard of the first four. "Umami" was only recently identified as the fifth flavor. (All other flavor sensations beyond these five are actually aromatics.)
- Sweet. This one is pretty familiar - think of sugar.
- Salt. Think of the way table salt tastes.
- Sour.Think of lemon or vinegar.
- Bitter. Think about baking cocoa, tea that has steeped too long, or aspirin.
Coffee can, and often does, exhibit all of these flavors, and part of the joy of cupping is how they interplay on your pallet.
Acidity is best described as the bright and zesty sensation found in coffee. It can range in intensity from low (gentle) to high (striking), depending on the origin, cultivation, processing and roasting of the beans. Important to note is that the acidity described in coffee is actually "perceived acidity" and is not related to the pH of the coffee itself; coffee has a pH of 5.7, which is similar to white rice or beer (a pH of 7 is neutral).
Beyond the intensity of the perceived acidity in coffee, there are also several different types of acids present that we pay special attention to:
- acetic acid (like vinegar)
- citric acid (like lemon and other citrus fruits)
- malic acid (like apples)
- quinic acid (which is slightly bitter, like the quinine in tonic water)
- phosphoric acid (like carbonated beverages or cola)
- lactic acid (like the sour flavors in dairy products - sour cream for instance)
Mouthfeel can be described as the perceived thickness of the coffee on our pallets. Thin coffees have low mouthfeel, and thick coffees have high mouthfeel. Imagine for a minute the difference in thickness from skim milk to whole milk, or from light maple syrup to molasses. When we grade coffees, we grade based on both the quality of the mouthfeel and its intensity. Some coffees can have high mouthfeel, but may also be gritty and granulated. Likewise, some low mouthfeel coffees can be very smooth and satiny.
Cleanliness in cupping can be described as the absence of defects and inconsistencies in a coffee sample. If the coffee was processed correctly it should have a refined taste. Some of the defects that may be found in coffees are over-fermentation (of fruit flavors), phenolic (chlorine-like flavors), Rio (iodine-like flavors), earthy flavors (like dirt or soil), and many others. Some defects are so intense that just one defective bean can negatively affect the flavor of an entire pot of coffee.
This is, quite simply, how well the coffee's different attributes intermingle. Is one aspect of the coffee too intense, like acidity? Or does the sweetness of the coffee blend well with the mouthfeel? After focusing on each individual attribute of the coffee during cupping, the balance category can be helpful for getting a cupper to look at the coffee as a whole.
Aftertaste is a little easier to understand than acidity or mouthfeel. Essentially we focus on the qualities and flavors left on our pallets after the coffee has either been spit out or swallowed. Is the aftertaste similar to the flavor of the coffee when it was on your pallet? Has it gotten sweeter or bitterer? Is it prolonged or does it slip away?
Beyond being responsible for analyzing the coffees we are looking to import, our Quality Control (QC) team does many other things to make sure that our coffee is of the highest quality. Production cuppings are an important aspect of the day-to-day in the QC lab. Every day the QC team joins forces with members from the roasting team to cup all of the production roasts from the day before. In doing so, we know how our coffees taste over time, we are able to check for problems with the beans themselves, and we are able to easily keep track of how the beans are roasting. From the time we start roasting a lot of coffee (one lot equals 37,500 pounds), to the time we roast the last batch, we will have cupped that coffee upwards of 100 times.