Over the last decade or so, advanced processing methods have become a hallmark of specialty coffee. If you have noticed a proliferation of terms like “anaerobic fermentation” and “thermal shock” on coffee packaging in recent years, you’re not alone.

Demand for these coffees largely stems from continued interest in unique and unusual flavour profiles. This ultimately drives some producers to experiment even further – effectively redefining existing processing methods or creating entirely new ones.

Innovation is an inherent and welcome part of the industry, especially at this level of the supply chain. But as some producers continuously tweak their processing methods to differentiate themselves in the market, the risk of miscommunicating how they achieve certain flavour profiles can increase.

This then begs the question: is it important that roasters know exactly what these new experimental processing methods involve? And if they don’t, how does this impact the consumer? Roland Horne, founder and CEO of WatchHouse, and Vicente Mejia, founder and CEO of Clearpath Coffee, give their insight.

You may also like our article on what roasters need to know about lactic fermentation.

How the market for experimentally processed coffees has diversified

There was a time in the coffee industry when honey processing was considered unconventional (with the exception of Costa Rica, which pioneered this method in the late 2000s). In today’s market, however, this technique is one of the “big three” alongside natural and washed processing.

This shift demonstrates the impressive level of innovation that has taken place in coffee processing over the last nearly two decades. As producers developed new methods to stand out in the market, consumers were exposed to more interesting and complex flavour profiles. 

Demand started to increase, and competitions like the World Barista Championship further fuelled interest. At the 2015 event, winner Sasa Sestic used a carbonic macerated Ethiopian Sudan Rume in his routine, which thrust experimental processing into the spotlight.

Like other advanced processing methods, carbonic maceration leverages fermentation to amplify certain flavour attributes or introduce new ones – broadening the spectrum of coffee flavour in ways rarely achieved on a commercial scale.

In the years since the 2015 WBC, the number of advanced processing techniques has exploded in specialty coffee. Some of the most notable examples include:

• Anaerobic fermentation – an increasingly popular processing method where producers control fermentation in a low-oxygen environment
• Thermal shock – created by Diego Bermudez, farmers wash cherries in hot water (at around 40ºC or 104ºF) before immediately running them under colder water (at around 12ºC or 54ºF)
• Lactic fermentation – a type of anaerobic fermentation where producers encourage the growth of Lactic Acid Bacteria (LAB), which converts simple carbohydrates into lactic acid

The push for experimentation with coffee processing is still ongoing. Terms like “anoxic” and “acetic” fermentation are increasingly appearing on packaging as producers look for new ways to manipulate flavour and improve cup scores.

Can we strictly define these new coffee processing techniques?

If you ask coffee professionals and enthusiasts to describe most experimental processing techniques, it’s likely that many will at least be able to provide a loose definition. But given that more producers are putting their own spin on advanced processing methods, as well as creating new ones, it’s become increasingly difficult for the wider industry to keep up.

Moreover, the similarities between certain processing methods can make it difficult to fully distinguish between them. Anaerobic and anoxic fermentation, for instance, essentially rely on very similar conditions and can create almost identical flavour profiles – further adding to confusion.

This is an understandable concern for roasters in particular. Often acting as the bridge between consumers and the rest of the supply chain, they are responsible for communicating as much information about their coffee as possible.

Roland Horne is the founder and CEO of WatchHouse in the US and UK, which recently celebrated its tenth anniversary. He confirms that it can be difficult for roasters to know exactly what new experimental processing methods entail.

“Most roasters don’t have the opportunity to visit farms that are carrying out experimental processing,” he says. “Since they’re never exposed to these methods firsthand, and there are no industry standards for naming them, there is little agreement on what they actually mean.”

Vicente Mejia is the founder and CEO of Clearpath Coffee, a specialty coffee exporter in Colombia. He agrees with this perspective, saying: “There are a lot of complex steps in coffee processing and most roasters don’t have the time to learn all the details.”

Do roasters need to fully understand them?

Consumers certainly want to know more about experimental processing methods and how they impact flavour profile. But do roasters need to share information in meticulous detail?

Vicente doesn’t think so, and believes it actually detracts from more pressing issues in the industry.

“The bigger problem is the lack of transparency about infused and co-fermented coffees,” he says. “Some farmers claim they can produce certain flavour notes through fermentation alone, but in reality, they are adding ingredients to achieve these results.”

Ultimately, there’s the fear that if infused coffees aren’t marketed or sold transparently then consumers will perceive these flavours as inherent to terroir and variety. This would be an inaccurate representation of the coffee, and could mislead perceptions of similar processing methods or flavour profiles.

Roland, meanwhile, believes the language used to describe advanced processing can muddy the waters even further.

“Since some of these processing methods are so new, there’s a changing nomenclature that creates a lot of unnecessary words instead of focusing on what is really important,” he tells me. “Instead, we should emphasise that these coffees are fermented in a controlled environment for a specific period of time at a certain temperature with a clear flavour goal in mind.

“I think it’s less important that we’re specific about 96 hours versus 72 hours, 25ºC versus 20ºC, or which strains of bacteria are used,” he adds. “I think this only adds to confusion.”

Similarly, Vicente highlights that most consumers don’t derive a lot of value from learning specific details about processing.

“The end consumer doesn’t need, and in most cases doesn’t want, to know all the details of a very complex fermentation process,” he says. “Instead, we need to make specialty coffee more accessible and enjoyable.”

Establishing a feedback loop

Although Roland and Vicente both agree that roasters don’t need to fully understand new experimental processing methods, this doesn’t suggest that less transparency is more valuable. 

In fact, the opposite is often true. Two-way communication between roasters and producers will inevitably make it easier to cater to changing consumer tastes and preferences, and ensure novel processing still meets market demand for differentiated flavour experiences.

“Creating a feedback loop means we can learn from each other and improve our processes,” Roland explains. “We can inform producers about what our customers think of these coffees so that they can adapt their processing methods.”

Conversely, producers can share information with roasters about what does and doesn’t work for them. Building trust in the partnership reassures producers that they can ask for more support or resources to carry out certain experimental processing methods, or to experiment with creating their own, so that they don’t have to absorb all the risk.

In the years to come, we’re likely to see more and more advanced processing methods create new and diverse coffee flavours. As demand increases, it’s important that roasters have a baseline of knowledge about what these techniques involve.

But understanding the specific nuances of novel processing is often unnecessary. Instead, to add more value to the industry, roasters and producers can work closely together to offer differentiated sensory experiences.

Enjoyed this? Then read our article on why transparency is key for infused coffees.

Photo credits: Darren Rowlands, Massimo Shyrbi

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