Coffee 201
How To Taste Coffee: Part 3, Bitter-Sour Confusion
Much of this content is from James Hoffman’s A Beginner's Guide to Coffee Tasting, an academic paper written in 1979, as well as the delightfully-named Society of Sensory Professionals. What a time to be alive.
OVERVIEW
This week, we’re talking about a peculiar intersection of theory and practice, with a good dose of vocabulary thrown in. It’s a common point of confusion that is called “bitter-sour confusion”. We’ll define what that is and then talk about why it matters to YOU.
What do we mean by “Bitter-Sour Confusion”
Here’s an explanatory quote from James Hoffmann to start us off. If you want to actually hear him say these words (and check the accuracy of my transcript), this is a link to the timestamp.
This is what he has to say about this concept of “bitter-sour confusion”:
“There is quite a common phenomenon in the general population which is called bitter-sour confusion. Where a lot of people, especially when tasting sour coffee, will describe it as bitter, because it’s unusual to most people to describe a coffee as sour. So sour-bitter confusion is pretty normal. Again, if you’re perceiving it strongly down the sides of the tongue, if it’s causing a little bit of salivation, it’s likely to be acidity. Now, I’ve come across sour-bitter confusion quite a lot in my professional life [...] that’s the language someone will reach for to describe what they don’t like.”
Here’s a more academic quote from the Society of Sensory Professionals, an organization I will never get tired of referring to by name. Here, they’re discussing the findings from that study:
“One hypothesis is that the subjects have more cultural experience with sweet and salty foods than sour and bitter foods, allowing their perception of sweet and salty to be more clearly developed than sour and bitter. A second hypothesis is that subjects are more familiar with sucrose and salt in their pure forms than citric acid and quinine sulphate [used in the testing], again allowing the subjects to better develop their own personal concepts of sweet and salty versus sour and bitter. A third hypothesis involves the incorrect cultural labeling of typically sour foods as bitter, as in the case of bitter lemon. In regards to these hypotheses, the authors concluded that the sour-bitter confusion can be attributed to a lack in the clear understanding of the definitions of sour and bitter rather than a physiological defect [i.e. it’s not a problem of tasting different things, but a problem of definitions.]
Enough Technical Language
That’s probably as scientific as we’ll ever get here, but what it demonstrates is what many in the specialty coffee industry have concluded: issues of palate development can be resolved with more experience tasting coffee. Sour-bitter confusion is one of the biggest areas that is going to be helped by you and a fellow barista tasting the same coffee. Let’s give an example of this.
If one of you says “oh, this is really sour” and the other one says “to me it tastes bitter” there’s a couple things you could conclude. The first thing, and something I occasionally hear on our team, is the “God only knows” response. “You taste bitter, I taste sour… the world is just one big cosmic mystery with espresso in it” and then we walk away and we conclude that there’s no way to dial in this espresso. That’s probably not going to help in the long run, and it’s also not accurate. “But how could two people taste the opposite thing?” Well, what if they aren’t tasting the opposite thing? That leads to the second conclusion.
The second conclusion you could reach is that, perhaps, you’re using different words to describe the same sensation. That’s why the study above is so important. Sour-bitter confusion, it says, is not a physiological defect, meaning it’s almost certainly not the case that two people are tasting different things. Instead, dig a little deeper. Think about what the coffee feels like in your mouth, where you’re feeling sensations, and compare that with someone else. You might just discover that what you’ve always called “bitter” is actually caused by acidity, making it better described as “sour.” Or vice versa.
Practical Tips
Assume you and your fellow baristas are tasting the same thing.
The quickest way to undermine your confidence as a barista is to assume something is wrong with you (or your coworker). It’s very normal to need to get on the same page in terms of the vocabulary you use. This is called calibrating the team and it only happens when we taste coffee together and talk about it.
Don’t feel bad.
For whatever reason, this “sour-bitter confusion” can make people feel like they’re dumb. I mean, what could be more embarrassing than someone saying the coffee tastes sour and you shout out that it tastes bitter? You’re not dumb. Getting to the place where you can accurately identify flavors is a matter of practice, and this is something you can practice. You got this! Try dialing in with a coworker this week.