Our body is complicated.
When we drink a cup of coffee, cause from all five senses turn into signals in the brain, travel through complex circuitry and produce what we call flavor.
As you’ve probably realized if you’ve worked in coffee for a long time, not everyone perceives the same thing when tasting coffee. Individuals vary based on their level of experience, their genetic, how they are feeling that day, and many other factors. So, is it possible to form an agreement on exactly how a particular coffee tastes?
In other words, we can , whose perception of flavor is inherently subjective, produce data with almost machine-like precision? Are we fooling ourselves when we aim for agreement between people who have different memories, emotions, and experiences? Let’s dig a little deeper into a few of these sources of variation.
First, it is well-known that genetic variation exists in taste sensitivity. If you’ve tasted one of those paper strips in high school biology class, you know what I’m talking about. There’s a gene for the receptor that determines how strongly a person perceives the bitterness of a compound called phenylthiocarbamide . Based on how intolerably bitter the strip is to a person, they are categorized as a “taster,” a “non taster,” or a “supertaster”.
However, the degree to which a person can taste PTC does not predict their sensitivity to other bitter compounds, let alone other tastes. There is some evidence that PTC taster status can influence coffee preference .
Taste bud distribution on the tongue also varies genetically. Some people taste more intensely because they have more taste receptor sites . Some people are “smell-blind,” or anomic, to specific odorants . Even our affinity for cilantro is partially genetic: people with a certain genotype more frequently report an unpleasant, soapy taste .
Memory and Experience
A person’s previous experience can affect which flavor attributes they notice when tasting a coffee. There are multiple elements to this, from subconscious associations to cultural culinary preferences.
Our past food experiences can influence our reaction to new flavors, including both how we describe them and their hedonic valence, or pleasantness. As any cupper knows, the more familiar we are with a particular food, the more nuances we notice.
What It Means for Coffee Professionals
So, how much does this matter for everyday operations, and what can we do about it?
Minimizing variation from other sources is also crucial in balancing individual variation. The more we can dial in the variables between cuppings, the more precise our sensory data and the more meaningful our conclusions.
The important part is not necessarily standardization across the entire industry, but clear communication within companies and within supply chains. Many coffee companies have developed extensive cupping protocols and standards. The terms and references in the Lexicon can serve as a useful complement to these. What is most important is that you can communicate within your own supply chain about what your product, the coffee, tastes like.
Academic sensory science, while a different exercise than cupping, can provide helpful principles. Here are a few practical tips, courtesy of Molly Spencer, one of the lead developers of the new flavor wheel:
Establish a training standard and calibrate yourself.
Consider implementing a procedure to make sure you’re all on the same page. When someone is learning cupping, test their accuracy. There is a lot of background flavor in a cup of coffee. spiking in flavor defects to a cup of coffee. This helps a novice cupper learn how the defects show up against the other flavor complexities of the cup.
Use warmup samples and references.
Everyone who has evaluated flavor knows there are just some days when you’re more “tuned in” than others. Get in the zone before cupping by warming up with a few samples before you begin scoring.for familiar tastes, it’s helpful for everyone on your cupping team to experience the same reference. When they are describing a certain word, like blueberry flavor, they’re all on the same page about what the definition of that really is. Training to a common standard helps mitigate individual variation.
Take frequent breaks.
In sensory science, it is standard to evaluate no more than 6-8 samples at once. Molly says, Coffee is so complex, there is physiological fatigue because your tongue and nose can only take so much. If you’re evaluating a lot of samples, try to space them out in time to preserve acuity.
consistency in protocol is key. Minimizing the variation in the cupping process details can help decrease the noise in your data. This can be especially important for companies with staff and roasteries in multiple locations.
Variation between tasters is a significant factor in coffee cupping, but it’s one that can be partially overcome by honing our process. Even simple practices like coding cups and taking a few more breaks can vastly improve the precision of our data. This precision helps us learn even more about the coffees we roast and serve, and ultimately communicate more specifically about their uniqueness and value.