An iteration of this article was first published in Standart Issue 35.
The edition celebrates water, a substance that is essential at every stage of coffee production, from growing and processing to shipping and brewing.

Fermentation and coffee go hand in hand. The simplest way to remove the pulp of the fruit without damaging the bean is to ferment. Doing so breaks down the structure of the pulp and can modulate the flavour in the bean. The current trend for non-traditional fermentations are a way for producers to add value to their crops, but with this comes extra expense and increased risk.

But this isn’t always the case…

“Making the simple complicated is commonplace; making the complicated simple, awesomely simple, that’s creativity.”

— Charles Mingus

There is beauty in simplicity, an elegance in its efficiency. But simplicity is difficult to achieve, it takes a creative and open mind to distil something complex to its barest bones. After all, how can we show how hard we have worked if the process isn’t complicated? This is a story about the search for simplicity, the journey to discover it, and because this is a coffee periodical, about a fermentation process; The Anoxic Water Pillow Technique.

Enter Miguel Fajardo Mendoza, a fourth generation coffee farmer. The family farm, Finca Santa Helena, sat amongst the hills of Risaralda in the central coffee heartlands of Colombia. The farm would do well, well enough for Miguel to pursue an education in Industrial Engineering and apply this first as the owner of a microbrewery before returning to the family business, coffee.

Coffee and beer have been linked for as long as most of us can remember, the parallels extend beyond the obvious similarities between the craft brewing movement and speciality coffee and into deeper, more fundamental levels.

As an example, consider the plethora of solutions to tune our water for brewing coffee. Recipes are available to accentuate mouthfeel, acidity (in its various forms), sweetness, floral notes… The list is somewhat endless. This however, is nothing more than “Burtonisation”, a term first coined in 1882 to describe the practice of adding gypsum and various sulphates to water, imitating the famed beer brewing waters of Burton upon Trent in England. So popular were the beers in fact, that in 1830 the Burton Brewers fought a libel suit against those falsely accusing them of adulterating their beers to enhance the flavours, something that seems strangely familiar….

(The irony of a tale about simplicity that has taken a detour is not lost on me, but I promise you it’s relevant.)

Perhaps the most pertinent and closest link between the two, and the one that truly ties together Miguel’s education, career as a brewer, and his life in coffee, is fermentation.

In 2011, Miguel along with the help of his friend Mario Fernandez started working at Finca Santa Helena, the family coffee farm, to understand fermentation and how to improve the quality but quickly ran into a scaling problem. The nature and size of the vessels, cement tanks 54 cubic metres in volume and lined in traditional majolica tiles made it difficult for two reasons.

Firstly, to control the heat generated when attempting to prolong the fermentation timeframes for such a large volume is difficult, Secondly by this time production at the farm was declining so the tanks were much larger than than the available harvest. Despite their work though, Finca Santa Helena was not to survive. The reasons were multitude, but primary amongst them was the end of the International Coffee Pact (ICP) in 1988. Farms such as Finca Santa Helena, designed for medium scale production, profited during the years of the ICP but were ill equipped for the new reality of a more volatile and fluctuating market. Attempts were made to pivot the production towards organic certified coffee. But a few years later, it was no longer viable financially, and had to be sold.

*Miguel walking through the now established coffee forest that is El Fénix*

Throwing himself into brewing led to new insights and a deeper understanding of fermentation. You see, when it comes to fermentation, control is everything and control of temperature especially so. His training as an Industrial Engineer came into play in understanding cooling systems, material properties, and measurement techniques; all utilised to optimise the flavour profile generated via the fermentation process.

Beer, like coffee, has a fermentation stage and also like coffee, it is very fickle when it comes to temperature. For example, the ideal temperature for brewers yeast (saccharomyces cerevisiae) is apx 17-24c, Too cold and the fermentation stalls, too hot and you can quickly generate overly sour flavours or kill the yeast. In both cases the batch is ruined.

But life works in funny ways and coffee has a way of bringing you back in. In 2011, purely by chance he met his future partners in what was to become Raw Material Coffee, a social enterprise company with the aim of empowering economic freedom for producers. Like many modern stories, it starts on Facebook, a chance invitation to visit a coffee farm that happened to be Finca Santa Helena and for there RM was born. At the core of this new company was El Fénix, a run down farm overlooking Calarcá in Quindío. Intended as a community wet mill and funded via an internationally successful Kickstarter, it grew into a test bed to continue learning about agronomy and fermentation to provide simple, practical and thoroughly tested methods that producers could use to add value to their crops.

At this time, the coffee world began changing at a rapid pace. The new generation of producers, like Miguel, were looking beyond the traditional knowledge bases and into complementary fields for inspiration. In 2015, a sudan rume processed using carbonic maceration achieved 1st place in the World Barista Championship, and the floodgates were opened.

It's a well known adage in motor racing, that “what wins on Sunday, sells on Monday”. This was the case in processing, as competitors searched for the next new thing and customers wanted to try the coffees that were judged to be so exceptional. And so in the years that followed, we saw the rise of anoxic fermentations, co-ferments, koji inoculation, thermal shock, saline washes, and flavour additives. A blizzard of ways that a producer can take a simple variety and by some clever processing, add value.

At El Fénix, Miguel and Raw Material had the perfect place to experiment on a new fermentation method that would add value for the producers whilst being simple and replicable. If this were a film we’d have a montage scene at this point. Jump cuts, and wipes of testing and failure, testing and failure, before the eureka moment and everyone high fives! But it’s not, and the process was longer, more laborious and driven by one key fact: in order to have an impact for the producers, it had to be easily replicable. In reality, this means it had to be simple.

*Hand-sorting cherry in tubs, in the early days at El Fénix*

Controlling fermentation temperature isn’t easy, and utilises the laws of zeroth thermodynamics;

“If two thermodynamic systems are both in thermal equilibrium with a third system, then the two systems are in thermal equilibrium with each other.”

Simply put, if we expose two systems, be they solid, liquid or gas of differing temperatures to each other, they will try to reach equilibrium.

The ability to raise or lower the temperature and mechanisms needed to do this, as well as the vessels and tanks used by larger farms and in other industries are expensive. Custom built metal tanks stored in temperature controlled environments, or cooling cools of continuously flowing liquid around the tanks are just two examples. So Miguel turned to his experience in brewing and engineering. Brewing had shown him the importance of controlling the fermentation and the complex systems that would be needed to achieve this, whilst the engineer in him allowed him to answer the crucial question:

On a farm in the Colombian mountains, what is at hand that is often a free resource and has good heat transmission properties?

The answer was simple… Water.

At the start, the solutions were too complex or needed large equipment. Cooling coils made from hose pipe and submerged into the fermenting coffee, were too thick to leach away heat and became far too dirty. Adding cold water directly to the fermenting beans, similar to how ice is added to sake fermentation tanks, only served to dilute the substrate and change the flavour profile, sometimes to the detriment of the coffee making it flat and muted. Dipping the tank in a large tub of cold water was possible, but practically difficult to replicate on a small level.

As we said at the start, simplicity is difficult and it takes an open mind to distil something as complex as coffee fermentation down to a simple process. Eventually, what it took was to step back and look at the materials at hand, and in doing so Miguel asked himself this question:

“What are the simple things almost every producer has to hand that we can use?”

*The process is simple, using items that are cheap and easily accessible for a coffee producer*

A tub or tank, some plastic sheeting and a little water. It seems almost too simplistic, but it works (and like all simple things are the result of years of trial and error).

First, attach a tap or make a small hole in the bottom of your tub, this allows some of the fermentation juices to escape helping to maintain the fermentation substrate and adds clarity to the acidity..
Next, add your coffee, as cherry or pulped depending on whether you’re going to dry as a natural or washed coffee, floated to remove lower density beans.
Take the plastic sheeting and place it over the coffee allowing it to extend above the top of the tub.
Fill the rest of the tub with water.

*Covering the plastic with water to create a vacuum seal*

The sheet provides a barrier between the water and the coffee and is thin enough to allow the water to fill the shape of the tub, forming a pillow of water above the coffee. In doing so the water can serve two functions; firstly it creates an anoxic fermentation environment, one low in free molecular oxygen. Secondly, the water in this state acts as a large heatsink, to draw heat away from the fermenting coffee, which regulates the risk of developing off flavours and also aids in prolonging shelf life.

The Anoxic Water Pillow technique is a creative use of basic materials to make a complex process so simple that it can be utilised anywhere in the world.

The proof of this simplicity is always in how easily others understand and can implement the concept. Have you really made a complex process easy to understand if others can’t grasp it?

*The water pillow technique at Izuba Washing Station, Burundi*

Following years of use at El Fénix and the Raw Material processing station Jamaica in Caldas, the chance to test this came during the COVID-19 pandemic. Miguel and the team at El Fénix exchanged videos and messages with their counterparts at Izuba, Raw Material's washing station in Burundi ahead of the 2020 harvest. There were to be no second chances here, the risk of spoiling a significant portion of the crop was great, could they communicate this simple process without having been there in person?

Put simply, yes. When the samples were milled the results were astounding, adding layers of complexity and flavour. The years of refining the process at El Fenix had achieved their goal, a complex process reduced to something simple enough to implement anywhere in the world.