Updated: Sep 27
In the realm of coffee production, the art of processing stands as a pivotal step. It is not only vital for upholding quality but also possesses the potential to either accentuate existing flavors or birth entirely new ones.
In recent times, we've witnessed a surge in coffee producers embracing a spectrum of experimental processing techniques. These methods encompass aerobic and anaerobic fermentation, carbonic maceration, and lactic fermentation. As these techniques increasingly carve their niche in the specialty coffee domain, it's natural to ponder the evolving trends in this realm. To glean insights into the future, I engaged in a conversation with two seasoned coffee experts from Mercon Specialty, a green coffee importer, and Brewed Behavior, a coffee consultancy. Before diving into the exciting world of experimental processing, let's first explore the foundational, traditional methods.
Traditional Processing Techniques
Washed Processing: Prevalent in regions like Rwanda, Kenya, Central America, and Colombia, this method involves meticulously removing the flesh and mucilage from coffee beans post-harvest. The cherries are depulped, stripped of skin and flesh, and then submerged in water for mucilage removal. Subsequently, the green coffee is left to dry on raised beds or patios. Washed coffees typically offer bright and pristine flavors, allowing the coffee's inherent characteristics to shine.
Natural Processing: This method thrives in areas where water resources are scarce, such as Yemen, Ethiopia, and Brazil. Ripe cherries are collected, sorted, and dried intact on patios, including the skin, flesh, and mucilage. Once the cherries reach the desired moisture level (around 10-12%), the beans are extracted. Natural processed coffees often boast fruity, sweeter, and fuller-bodied profiles, sometimes reminiscent of wine and with a richer mouthfeel.
Honey Processing: Particularly prominent in countries like Costa Rica, this method gained traction due to water usage restrictions imposed after an earthquake in 2008. Farmers had to adapt to reduced water consumption, leading to experimentation with honey processing. In this technique, a specific amount of flesh and mucilage is retained on the drying coffee. Pulped natural processing, similar in concept, was pioneered in Brazil. It involves removing the fruit and skin but leaving the mucilage intact, thereby expediting the drying process. Honey processing is hailed as a fusion of traditional and innovative methods, offering a spectrum of flavors and mouthfeel based on variations like black, yellow, red, pink, and white honey processing.
Exploring Experimental Processing Techniques
Scott McMartin, Director of Coffee at Mercon Specialty, emphasizes that experimentation isn't novel in the world of specialty coffee. Tradition and innovation have often coexisted to enhance quality and sustainability in coffee processing. However, recent years have witnessed a surge in more complex experimental processing methods, featuring additional variables and demanding heightened control.
Aerobic and Anaerobic Fermentation: Fermentation commences upon coffee cherry picking, but modern producers have harnessed it to generate diverse, enticing flavors. Aerobic and anaerobic fermentation are the dominant labels associated with experimental fermentation. The key distinction lies in the presence of oxygen. Aerobic fermentation incorporates oxygen, accelerating sugar fermentation. Conversely, anaerobic fermentation unfolds in oxygen-free environments, often hermetically sealed containers. This slow fermentation allows for the development of intricate flavors, resulting in fruitier, fuller-bodied coffees compared to traditional washed processing.
Carbonic Maceration: This technique, akin to anaerobic fermentation, involves sealed vessel fermentation with carbon dioxide flushing. Carbonic maceration yields highly fruity and wine-like flavors, along with herbal, floral, or tropical fruit notes.
Lactic Fermentation: Comparable to fermentation practices employed in products like sourdough bread and sauerkraut, lactic fermentation entails the addition of lactic acid cultures to coffee during fermentation. This approach is gaining traction, offering a creamier mouthfeel and yogurt-like flavors. Both lactic washed and lactic natural coffees are on the rise.
Double Fermentation: Popular in Kenya, double fermentation involves two fermentation stages. After depulping, the cherries undergo initial water fermentation for up to 24 hours. Subsequently, the mucilage is removed, and the beans undergo a second fermentation for an additional 24 hours. This method typically yields brighter, cleaner-tasting coffees due to more extensive mucilage removal.
Feasibility for Producers
Undoubtedly, increased fermentation levels introduce higher risks during coffee processing. Without meticulous control, over-fermentation can result in undesirable off-flavors, such as sourness, fruit rot, or subpar wine-like notes. Consequently, many farmers cautiously experiment with smaller batches, facilitating precise control. However, this approach can be financially taxing, particularly for small-scale producers. Scott McMartin notes that most producers thoroughly understand their production costs before venturing into riskier, potentially more lucrative processing methods. While experimental techniques can be labor-intensive and costly, they present opportunities for market access. However, traditional processing should not be abandoned entirely.
Producers should also acknowledge that the market for experimental processing remains relatively niche. Many suppliers at Mercon show interest in innovative methods but allocate them to a small percentage of their coffee offerings. Consequently, producers aspiring to embrace more fermentation in coffee processing should start with small-scale trials. Effective communication between farmers and roasters is pivotal when marketing experimentally processed coffees. Roasters typically market these coffees as limited editions or exclusive lots, necessitating a commitment to consistent processing methods for several years.
Consumer preferences and future outlook
The evolving landscape of experimental processing raises intriguing questions about changing consumer preferences. Traditional coffee enthusiasts might not readily embrace the diverse flavors, fearing a departure from coffee's innate character. Fermented flavor profiles might be an acquired taste for some consumers, analogous to the acquired taste associated with certain Scotch whiskeys. Within the specialty coffee realm, experimental processing has gained momentum, generating excitement among baristas and coffee aficionados. While these unique flavor profiles might not suit all traditional consumers, those who relish them are often willing to pay premium prices.
In conclusion, while experimental processing methods constitute a small fraction of overall coffee production, their popularity within the specialty coffee sector is undeniable. These methods, when executed skillfully, can unveil hitherto undiscovered dimensions of coffee. Producers seeking to scale in this domain should tread cautiously, ensuring the necessary resources, starting small, and recognizing that the market, though growing, remains niche for now. Reference: https://perfectdailygrind.com/2022/10/exploring-trends-in-experimental-coffee-processing/