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Experimental Coffee Fermentation on The Kona Coast

Updated: Mar 26, 2021

Innovation keeps tradition alive on the western slopes of Hualālai

Kona Coffee Farm in Holualoa Hawaii
Ulu Coffee Farm, 2020

It was the day before New Year's Eve when Phil called. I stood in a Chicago parking garage covered in the essentials; coat, gloves, hat, mask. He was calling from Hawaii.

"I've gotta tell you about this cup of coffee Kraig just gave me. Man, it was unbelievable—Absolutely unlike anything I've had before." He said with urgency. I went to visit Phil at the farm just a month ago to catch up and discuss next year's harvest and celebrate the final leg of our first year producing coffee for the small estate.

He talked about Kraig Lee, a long time Kona farmer and seedling supplier at Kona Farm Direct. Someone that Phil, founder and head farmer for Ulu, not only sources his Kona but learns a great deal from and tends to enjoy bouncing ideas off of. Even over the wind from his driving, I could hear Phil smiling from ear to ear. He continued without pause, "It was fermented with Champagne yeast. I think we're gonna do it with this last pick. We're going to try it with Ulu coffee.”

I froze with excitement. Watching an elevator pass, I recalled Phil's hesitancy the first time experimental coffee fermentation came up in conversation. It didn't go very far. At first, I couldn't believe it. How did this one afternoon with Kraig leave Phil singing such a different tune? Then I recalled Kona's culture and history of innovation with coffee cultivation.

Coffee Processing in Kona has always been a culture of pride, hard work, and self-sufficiency. The elevated slopes of Mauna Loa and Hualalai provide a thriving atmosphere for coffee to grow. And because of the friable volcanic soils, the meager two-mile stretch of land naturally evaded the late nineteenth-century agricultural shift to sugar. The machines needed to cultivate such ventures could not withstand Kona's precipitous terrain, which offered a reluctant opportunity for coffee in the area known today as the Kona district.

Following the Great Mahele or division of lands in 1848, Kona coffee would soon become an export of excellence and quality. With the introduction of family-owned farms, it populated into a hopeful place for independent business ventures. But the story of Kona coffee is one of perseverance and determination. Persistence led by Portuguese, Filipino, and Japanese laborers. These early-twentieth-century pioneers were harvesters that worked fields to become independent farmers. Many arrived in Kona without any experience farming coffee. But they looked to what others were doing and remained equipped with resilience and an eagerness to learn. Accordingly, setting the stage for the farming culture that thrives there today.

Despite the ideal microclimate for growing coffee, the quest for independence and the success of Kona's world-renowned delicacy relied heavily on working together as a community. Modernization and new processing methods were introduced to Kona early on and even more toward the end of WWII. Innovations like Fukunaga's pruning method and Jeeps to replace the Kona Nightingale didn't always come easy. But ultimately, Kona wouldn't have survived without adopting an open mind and consistently learning new ways to produce quality coffee. If there were ways to use less waste, be more efficient, and improve quality without sacrificing land or independence, it was likely to be explored.

With experimental coffee fermentation, Phil's contemplation wasn't because he was set in old ways. He doesn't have old ways. It wasn't that he didn't intend to strive for an even higher standard of quality. Or produce a more esoteric cup of Kona here and there. After all, he's an independent farmer of a third-wave mindset; really, anything goes as long as it's good for mother earth and makes a killer cup of coffee. But more or less, Phil is a guy that does things as they come, when they're meant to, much like the realization of Ulu itself.

So when suddenly he decided to pour Champagne yeast into the last pick of Ulu's first big harvest, I realized the experience Phil had that afternoon with Kraig’s coffee was eye-opening.

But what is coffee fermentation? What is its purpose in coffee production? And what was it about that cup of coffee that brought Phil to move forward with controlled fermentation?

Traditionally speaking, coffee fermentation, also known as "demucilagination," is a post-harvest step in the coffee process. Since coffee is a fruit, fermentation is an inevitable step to remove layers under the fruit skin in order to craft a drinkable product. For most farmers, fermentation serves as a primary function, a necessary means to an end. The way farmers execute this step varies considerably from region to region.

In Kona, farmers pulp the fruit, popping the seed out of its flesh, sending the pulped fruit to compost. Then, soak the coffee bean (seed) in water overnight to allow bacteria to eat away the slimy film, known as mucilage. This seemingly neutral step is actually one of crucial importance. Farmers meet big decisions during this stage of production. Because if poorly managed or left unattended, the coffee will impart undesirable flavors into the final brew, ruining an entire crop. These kinds of decisions often require a little luck, a lot of patience, and an explicit understanding of the climate and the coffee plant.

With flavor, the purpose for fermentation is widely recognized but little understood. Knowing things like fermentation time and temperature, among other coffee process methods, are passed down from generation to generation. Farmers today are, for the most part, still relying on regional traditions and techniques that haven't been updated since the 1960s and possibly even earlier. But recent studies show that controlling fermentation methods in coffee can actually have a positive effect and improve the overall quality, flavor, and consistency of a brew.

Lucia Solis, a microbiologist who specializes in coffee processing and fermentation design, notes that "If you look at this step as a mechanical process, you miss the opportunity that the microbe's metabolism can impart desirable flavors to the seed." That viewing fermentation as a neutral step is an opportunity lost to "enhance and supplement the hard work done in the field."

One of the controlled fermentation methods described to "enhance and supplement" is known as yeast inoculation. Essentially, adding natural yeast cultures to the beans before they soak. Sort of like adding yeast to bread to make it swell, adding yeast to coffee to enhance complexity. One should note that these new controlled fermentation methods are really just now breaking the mold in the coffee world. Farmers and scientists alike understand very little about how a controlled fermentation will affect a final brew. At least not until they can experiment for themselves. Something that coffee market prices will likely never support for the majority of producers.

Though coffee production, in general, is widely unexplored, there's no denying that coffee's flavor can vary significantly from region to region and even lot to lot. The possibilities for quality, consistency, and complexity in new controlled methods are boundless. And also relatively unknown. 'Flying blind,' if you will. One coffee farmer 100 ft. higher in altitude from another, using the same fermentation processes, can still have wildly different profiles.

So, as it were, one late December afternoon in Kona, hours after harvesting the last of the season's fruit, Phil tried a cup of coffee, unlike anything he'd had before.

"I hadn't even gotten out of the car before Kraig was shoving a mug of coffee through the window," Phil said. Eyes closed, it could have been "Chocolate or Strawberries, I don't even know." he recalled. "It was wild."

Perplexed and excited, he knew exactly what he was going to do next.

. . .

The perception of flavor that Phil experienced that day is Ulu, something that came to him. The gift of an idea, a force of creative energy that motivates, and the exciting unknown of what's to come of it. Pouring Champagne yeast into the last pick of 2020 seemed fitting after all. But ultimately, it was Phil's personal experience that would allow him to move forward with experimentation--exploring a new technique in a quest to seek unforgettable flavors with Ulu's estate Kona coffee.

Will this ever happen again? Perhaps. But as Phil would say, "One thing at a time."

Farmer on coffee farm, pruning coffee in Kona Hawaii
Phil Hodson, pruning coffee, 2021


Kinro, Y. Gerald (2003). A Cup of Aloha, The Kona Coffee Epic

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