The Specialty Coffee Association (SCA)’s Coffee Taster’s Flavor Wheel is arguably one of the most iconic resources in the coffee industry. The poster adorns the walls of cupping labs worldwide and has become a backdrop for most professional coffee training courses.

Originally published in 1995, the wheel has been the industry standard for over two decades. It was reworked in 2016, when it became arguably the largest and most collaborative piece of research on coffee flavour ever completed.

The wheel has undoubtedly come a long way in the past 25 years. But does it still cater to the complex needs of the multicultural, ever-evolving world of coffee? I spoke to three experts to learn more. Read on to find out what they said.

You might also like our article on colonial inequalities in the coffee sector.

An overview of the Coffee Taster’s Flavor Wheel: “Descriptive, not prescriptive”

The eponymous Coffee Taster’s Flavor Wheel was designed as a tool for the coffee taster. According to the SCA, the Flavor Wheel can be used either in casual tasting or professional coffee cupping. In either situation, the SCA notes that the key is to be mindful.

The SCA defines “flavour” as a combination of taste and smell. It is important to distinguish between aroma (linked to smell), taste (linked to the mouth), and flavour (a combination of both). Ultimately, the wheel acts as a guide to the sensory experience of coffee.

Peter Giuliano is the Chief Research Officer of the Specialty Coffee Association and Executive Director of the affiliated Coffee Science Foundation. He was directly involved in the development of the wheel as we know it today. 

He tells me that a common misconception about the Flavor Wheel is that it is about quality.  

“It’s not. It’s descriptive, not prescriptive,” Peter says. “The SCA cupping methodology is subjective because it’s about assigning value to the coffee. The lexicon and sensory descriptiveness of the Flavor Wheel are not.”

The first version (1995) was a lot more prescriptive. It was actually made up of two “sub-wheels”: “Taints & Faults” (defects) and “Tastes & Aromas” (attributes). 

Some 25 years on, the situation is very much different: we have one wheel and a lexicon. Both are the result of years of collaborative work, drawing on a combination of science, research, industry knowledge, and design.

A sensory analysis tool built on science, research and collaboration

The original Coffee Taster’s Flavor Wheel was first developed by the SCAA more than 25 years ago. Until 2010, the version in use was largely the same.

However, about 10 years ago, stakeholders started to realise that the wheel needed to be reinvented. The first step was building a lexicon. To do so, the SCAA turned to World Coffee Research for help.

The World Coffee Research Sensory Lexicon: What is it?

To put it simply, Peter says: “You need a vocabulary, or lexicon, to train tasters. 

“You then establish a reference. For example, for blackberry, you use a specific type of blackberry jam. That way even someone who has never tasted blackberries themselves can make the connection. The lexicon is about building a common language.”

The World Coffee Research Sensory Lexicon is the product of a collaboration between dozens of professional sensory panellists, scientists, coffee buyers, and roasters. It was developed by World Coffee Research (WCR), the Sensory Analysis Center at Kansas State University, and the Specialty Coffee Association of America (SCAA). 

Peter tells me that there was a fair amount of scientific rigour associated with the process and methodology. 

“They tasted around 100 coffees and identified their attributes over the course of a year,” he tells me. “It became The World Coffee Research Sensory Lexicon, and the basis of the new Flavor Wheel.”

The lexicon identifies 110 flavour, aroma, and texture characteristics present in coffee, and provides references for measuring their intensity. This groundbreaking tool has shifted the way our industry thinks about and describes coffee flavour. 

The SCA Coffee Taster’s Flavor Wheel

Now that a lexicon had been built, the SCAA needed to turn it into a user-friendly tool: a flavour wheel. 

This time, they turned to the prestigious Food Science and Technology Department a thet University of California, Davis (UC Davis) for help.

The UC Davis team used a novel adaptation of traditional sensory and statistical methods to reorganise the new coffee Sensory Lexicon into scientifically valid clusters. This was the foundation for preparing a new, updated flavour wheel.

According to an article in the 2016 Journal of Food Science, it took 72 experts to sort the flavour attributes of the lexicon. The data was then compiled and arranged into a wheel.

Dr. Jean-Xavier Guinard is a sensory scientist and a consumer researcher at UC Davis. His research was instrumental in the design of the new Flavor Wheel. He explains that UC Davis was involved in the development of wine, beer, and honey flavour wheels, too. 

“This one really hit the mark,” he says. “It’s comprehensive and well-embraced by an industry thirsty for scientific and technical tools to refine their craft.” 

The final design, a kaleidoscopic picture of coffee flavours, was the work of One Darnley Road, a creative agency based in East London. Each colour and shade was carefully selected with the intention of best matching the corresponding flavour. 

An iconic design: “A symbol of the glory of specialty coffee”

With the completion of the Flavor Wheel and its new, vibrant design, the SCAA had turned an historically complex and technical tool into a fresh, marketable accessory. 

“The SCA did a fantastic job with that,” Jean-Xavier says. “They succeeded in reaching all corners of the industry.”

Peter adds: “Suddenly, what was meant to be a tool became a symbol of the glory of specialty coffee, and of us as an organisation.” The poster went viral; people started taking selfies with it and even bought t-shirts bearing the design.

However, Peter notes that there is a flipside to this success: in some instances, the wheel has become more popular for its design, rather than its utility. He admits that in many instances, the poster has become decorative, rather than practical. 

Arguing semantics: “Language and culture bias perception”

The revised Coffee Taster’s Flavor Wheel and the associated lexicon have been an undeniable success. But success comes with its fair share of scrutiny. Some argue that the Flavor Wheel’s language is not inclusive enough.

Peter tells me that one of the problems with the first versions was the use of antiquated or obscure language that just wasn’t familiar. This made it much less accessible as a tool.

In comparison, Peter says that today’s version is meant to be far more inclusive in terms of language and vocabulary. However, he acknowledges that it may be a little too US-centric. 

“Blueberry and maple syrup, for example, are very American references,” he tells me. “I think there will probably be some changes in the future, sensitive to more internationally accessible attributes.”

Jonathan Vaz Matías is a traveling AST trainer, a coffee consultant, and the CEO of Acuerdo Project. He has also developed the Fruits Flavour Wheel; Jonathan describes it as “a halfway mark between a wheel of aromas that is culture-specific and the generalised version developed by the SCA”.

For Jonathan, while the concept of the SCA Flavor Wheel and the World Coffee Research Sensory Lexicon are fantastic resources for the industry, they are not inclusive enough. 

“The lexicon is super important. We need a scientific method and language to communicate,” he says. “But the problem is that we are using a language that many people don’t understand, with a massive cultural bias.

“Your language and culture biases your perception. You need to adapt descriptors,” Jonathan concludes, noting that the experience of flavour is “deeply personal”.

To give me an example, Jonathan tells me about the first time he tried Kenyan coffee. “It was very sour, acidic, and I could taste berries. I was told that I should say it tastes like blackcurrant, but that was not a taste reference for me; I had never had one!” 

Ultimately, Jonathan argues that we can use a wider range of descriptors than those offered by the SCA and WCR. 

Who is the Flavor Wheel for?

The wheel is intended mostly for specialty coffee professionals and researchers; people who have been trained to use a common vocabulary of scientific descriptors. In that context, it works.

However, Jonathan tells me that he thinks the wheel is more for coffee sector researchers than other industry professionals. 

“It’s useful in a closed community where all speak the same language. But does it apply in the real world?” He asks. “We need to calibrate and reference according to [the] users.” 

He argues that the way the tool is now is too limiting and exclusive. Baristas, coffee shop owners and roasters could end up being alienated, meaning that all the amazing research won’t have a real impact in the end. 

On one hand, training a tight group of professionals to use a common language is what makes the Flavor Wheel work. On the other, we have to ask: is there a risk of creating an echo chamber, by training an elite group of people on one line of thinking? 

Jean-Xavier says: “The Flavor Wheel doesn’t cover everything and doesn’t pretend to. But one of the pieces the SCA has perhaps not taken sufficient advantage of is consumer outreach. It could be promoted a little more extensively to consumer groups.” 

At the end of the day, Jonathan says, what matters most is how many people can find the wheel useful, and how well it can serve the industry. 

There’s no need to reinvent the wheel; but can we improve it?

While the Flavor Wheel is based on science and research, it is also a sensory tool and very much a human product, which makes it imperfect by its very nature. As the industry evolves and the geography of consumption shifts, the language of coffee will naturally change, too.

“We’ve always thought of this tool as a work in progress,” Peter says. “It’s open to revision. If there’s a better way to do it, we’re open to it. Flavour diversity is very important to us.”

Jonathan, however, suggests that the Flavor Wheel is too targeted and not inclusive enough. He says that his Fruits Flavor Wheel was designed in a response to this, and notes that other industry stakeholders and entrepreneurs have designed their own for the same reason.

“In the end, it’s about communication that is efficient and accessible to all,” Jonathan says. “[For example], the SCA wheel offers 18 descriptors for fruit; the Fruits Flavor Wheel offers 95.” 

He goes on to explain that his descriptors are fruits that can be found on any continent around the world, and not centred around one particular continent or country.

Jonathan also points out that the Coffee Taster’s Flavor Wheel balances flavour, taste, and aroma, noting that this can be confusing. 

However, it remains important to recognise that despite these alternatives and improvements, there’s no space to evolve without the landmark that is the SCA wheel. The concept of a flavour wheel alone is, in the grand scheme of things, revolutionary and still comparatively young. It remains incredibly valuable for the industry, as does the research behind the WCR lexicon.

The SCA Coffee Taster’s Wheel might not be perfect, but it has come a long way since 1995. The most recent version marks a huge turning point for specialty coffee, and shows the sheer amount of interest in determining a common language for flavour.

No matter the criticisms, it’s important to recognise that developing a global descriptive language for the sensory experience of coffee is incredibly difficult. The SCA and its partners have done a great job in rising to the challenge. 

But while their efforts have largely been successful, there is still work to be done. The coffee industry continues to evolve at a rapid pace, and the tools and language we use must adapt to remain representative, useful and inclusive. Just how things will change in response to that remains to be seen – but there’s no doubt that it’s an interesting challenge to observe.

Enjoyed this? You might also like our article on Slow Food philosophy and coffee.

Photo credits: Peter Giuliano, Specialty Coffee Association, Acuerdo Project

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