1.- Origins of fermentation.
 
Fermentation is older than any ancient civilization that we know of today. Several archaeological excavations have found jars with the remains of wine that are approximately 8,000 years old.
 
After much trial, error and careful observation, almost all civilizations began producing fermented beverages (and foods as well), but mainly wine and beer. It started with the fermentation of water with honey in Asia, then the Egyptians, Babylonians and Romans used grapes to produce wine, the Chinese used rice instead to produce wine and other civilizations produced beer with barley. Chicha was produced in South America, through the fermentation of corn.
 
In those days people started to leave fruits and grains in closed containers, because they knew that after a long time, that would turn into wine or beer. But no one really understood how the recipe worked. The process was called fermentation, which comes from the Latin "Fervere" which means "To Boil". The name was created because after a time of leaving the fruit in the vessels, people saw the mixture bubbling, so they thought it was boiling.
 
Producing fermented beverages at the time was complicated, if the mixture didn't stay long enough in the container, the result would not have alcohol at all; but if you left it too long, it was undrinkable. After much observation, people understood that temperature and air exposure were critical to the fermentation process.

​2.- What is fermentation.
 
First of all, we must say that the general definitions of fermentation do not apply directly to coffee. This is because coffee is not a fermented beverage like wine or beer, but coffee production processes USE FERMENTATION AS A TOOL, either to break the mucilage structure and facilitate the execution of a certain processing method (Washed, Giling Basah, etc) and/or directly influence the quality and flavor of the bean (Natural, Honey, Washed, Giling Basah, Experimental, etc). Almost all the different coffee processing methods in the world use fermentation in one way or another, with the sole exception of mechanical washing.
 
So now that we've made this exception regarding to coffee, let's go back to the more general concepts of fermentation. In very simple words, fermentation is a TRANSFORMATION of a complex element into another much simpler one. OK, that's perhaps too simplistic! :)
 
Now more in depth: fermentation is a metabolic process that converts sugars into acids, gases or alcohol.
 
Louis Pasteur, the father of microbiology, who is responsible for all our understanding of fermentation today, pointed out in 1856 that there are two types of fermentation: Alcoholic and Lactic Acid. Alcoholic fermentation occurs through the action of yeast, lactic fermentation occurs through the action of bacteria.

3.- Coffee Fermentation.
 
As we already know, fermentation is a metabolic process of transformation of simple sugars into acids or alcohol. This can be divided into two main groups: alcoholic fermentation (produced by the effect of yeast) and lactic acid (produced by the effect of bacteria). But the variety of microbiota (that is, yeast + bacteria) that are involved in the fermentation process of coffee, is still poorly understood from a scientific point of view.
 
A study that we could find on "Mucilage Fermentation" from 2004 in Nicaragua (SC Jackels. Dept. of Chemistry, Seattle Univ.), Took samples from 7 different lots that were fermented in concrete tanks for periods between 10 to 24 hrs at a temperature of between 21 - 23 ºC; and concluded that: (1) in all samples the glucose level decreased constantly throughout the entire process; (2) that the levels of lactic acid and / or ethanol increased exponentially only in the last 3 hours of the fermentation process; (3) and perhaps the most important discovery, the PH level is a fundamental factor in determining when the fermentation would be complete, without developing unpleasant over fermented flavours (produced by acetic acid and ethanol), and this value on average was PH = 4,6.
 
The coffee microbiota has spread throughout the world along with its plants through human activity (Current Biology 26, 965–971, April 4, 2016). But also, the more "artisan" styles of coffee fermentation have generated several microbiota strains with independent origins. In other words, the bacteria and yeast found in Africa are different from those in South America, and these are different from those in Asia. These could play a much more important role in the development of unique cup profiles for different origins of the world, or what would be known as the "MICROBIOTIC TERROIR".

​4.- Types of Fermentation.
 
With this post we end this series of four articles where we have tried to understand fermentation in depth. First through its history, then understanding what exactly is fermentation, following on how it is used in coffee production; and finally we will see in detail the types of fermentation that are currently used around the world of specialty coffee.
 
We must say that the following types of fermentation, in the industry are called "experimental processes", and refer EXCLUSIVELY TO THE ENVIRONMENT where the coffee is fermented, and not to the metabolic process of fermentation, which by definition is anaerobic, meaning, free of oxygen.
 
AEROBIC FERMENTATION: Implies that the fermentation stage is carried out in an environment high in oxygen. It is the most widely form of fermentation used in coffee; and it occurs during the FW process when we dry-ferment (without water) coffee in a tank, or when we dry natural or honey processed coffee on African beds or concrete patios.
 
ANAEROBIC FERMENTATION: Implies that the fermentation stage is carried out in a low or no oxygen environment. An example, take place during the FW process when we wet ferment (soak) coffee in a tank with water.
 
LACTIC FERMENTATION: Generally is carried out in a steel tank in an anaerobic environment. After pulping, it's assumed that only the especies of bacteria which transform  glucose into lactic acid are alive. There is little scientific support to this, since there are other microorganisms (like yeast) that can also survive in low oxygen environments and could also influence the final result of this type of fermentation.
 
CARBONIC MACERATION: Process borrowed from the French wine industry, and made popular by Sasa Sestic WBC 2015. The process is similar to that described above, but fermentation is done with the whole cherry without pulping. Fermentation here may take days or even weeks since the cherries are left intact.
 
YEAST FERMENTATION: As we have said, yeast and bacteria are microorganisms present in the soil, water, air, tank, pulp, etc. But this process refers exclusively to the adhesion of commercial yeast strains (generally the one used in the wine industry) to the tank, where a wet anaerobic fermentation is being carried out.
 
To wrapped out, we just want to say that all these experiments are great, because this industry has been built and grow on experimentation; but not because a process has a "funky" or "trendy" name it will be better than another which is simply called "washed" or "natural". Let's select our coffees by their cup profile and not by their names.
 
Honorable mention to many people from whom we borrow info (all references on our blog), and especially to Lucia Solis from the "Making Coffee" podcast.
 
THE END

​What is moisture? Moisture content is the amount of water (in the form of vapour) in a sample, given as a percentage of the sample's original weight. In coffee, there is no exact standard for an ideal moisture content, but a generally accepted range goes between 10-12%, with some important exceptions like Sumatra being closer to 12.5%; And Ethiopia and Kenya being closer to 9,5%.
 
What is density? Density describes how much space a coffee bean takes up (its volume), in relation to the amount of matter in that same coffee bean (its mass). Denser beans are more flavourful, because its cellular development slows down the higher in altitude it's grown (because it’s colder), which means the coffee retains more sugars and nutrients. The farther from the Equator, the lower you need to go to grow high density coffees.
 
What is Water Activity? The water activity describes the energy state of water in a specific coffee sample, and hence its potential to participate in biochemical reactions and growth of microorganisms (mold, bacteria, etc.). It is used to predict the stability and safety of coffee and food in general, with respect to microbial growth and rates of deteriorative reactions.

​Flavour is the main and most important criterion for evaluating quality in coffee, so our goal here, is to understand how these three factors will affect your roasting, flavour development and its correlation.
 
Why are these parameters important when roasting? Basically, because the beans will react in a certain way according to different levels of moisture and density (water activity is directly related to moisture, so for the sake of the roasting part of the article, we’ll just focus on moisture and density) when heat is applied. Let see it more in detail:

​There are two laws of physics that are worth understanding:
 
1.- Heat transfer more quickly through denser objects.
2.- Moisture is a great conductor of heat, as it transfers faster in water than in air, for example.
 
Let’s imagine that we have two 100 ml cylinders, filled up to the top with coffees that have the same moisture content, 10%. Now let’s say that one of these coffees is a low altitude washed Arabica from Brazil, and the other a high altitude washed Arabica from Ethiopia. These two coffees have exactly the same moisture content, but the densities are very different, the Ethiopian being denser, will have more water in it than the Brazil.
 
It is important to understands that the correlation of these two parameters (moisture and density) will tell us how to better approach roasting a coffee. Moisture content alone is useful for understanding and predicting a series of events throughout the coffee production chain, but for roasting alone, density is the first and main information you should get.
 
This is a complex topic that deserved a longer article, more discussions and more research no doubt.

​There is a simple rule in the world of environmental sustainability, and this is: "If any waste or pollution of any kind is generated, someone further down the production chain will be affected and will have to pay for it."

In an industry such as Coffee, which generates revenues of more than USD100 billion a year, curiously, it is not the big corporations the ones called to lead the changes in the area of environmental sustainability; but is us! The small companies focusing on high quality coffee on the specialty niche. Although we do not contribute significantly in terms of pollution or waste and we take a very small percentage of the revenue mentioned above, we cannot wait for Nestle or Starbucks for example, to take the measures that will make a real difference in this regard. We could wait a lifetime and more for this to happen.

​Specialty coffee is not only about serving a quality cup, it also tells the story about how the lot was sourced, if an ethical price was paid to the producer, if the given traceability is relevant and honest, if the logistics are green and efficient, if the production of that lot did not include any forced or child labour, or if it generated abuse or poverty of any kind.

Undoubtedly, the cornerstone of this whole idea is quality, without it, all the subsequent philosophy falls apart. But when we get the quality coffee we want, it is essential to work on the conceptual aspects of specialty coffee and make them prevail.

In environmental matters, we have committed with two emblematic projects to which we contribute in a humble but consistent manner. We donate 2% of our annual sales to two foundations that work on the protection of Elephants in Kenya and Gorillas in Rwanda and their habitat.

We will never ask you to support us financially to give for these projects, but we want you to know that when you buy a Kilimanjaro Specialty Coffees bag, 2% of the price you pay goes directly to the protection of Elephants in various regions of Kenya and Gorillas in the Volcanoes National Park in Rwanda.

Enjoy your African coffee and protect the planet, because it is the only one we have.

​But as in all areas of life, nothing is perfect, and the Kenyan coffee industry is no exception. It is no mystery to anyone that agriculture is the cornerstone of the Kenyan economy, and the cooperative movement has a solid footprint that can be traced until just after independence in 1963.

Today, there are about 5,000 agricultural cooperatives throughout the country, and of these, 421 correspond to cooperatives of smallholders coffee farmers, with a total of 570,824 active members. The cooperative movement seeks to generate wealth, food security and employment, which ultimately results in poverty reduction; But the harsh reality is very different. With few exceptions, due to corruption and mismanagement of many boards of directors, these objectives are far from being met, and coffee farmers have been affected by decreasing their income in such a way that many have stopped growing coffee and the vast majority are very disappointed of the crop.

​The main reason for this phenomenon, is not the lack of customers who would pay good prices, because as importers or roasters, it is at this origin where those who go in search of exceptional coffees, pay on average the highest prices in the world. The problem lies in how that wealth is distributed within the productive chain in Kenya, and the inability of the farmers to question the expense of the cooperative, the miller, the marketing agent or the exporter.

On our recent trip we met cases, in which the manager of the coop at the end of the season pointed out that after selling all the coffee (at a reasonable price), expenses had been deducted and coffee growers owed money to the cooperative !!! Which also means that for the present campaign, there was no money for fertilizers, pesticides, training, etc. Generating a negative spiral of destruction which will be almost impossible to leave, unless these farmers leave coffee cultivation for other cash crops.

​This is just one example of the very many that can be found traveling through the coffee areas of Kenya. We believe that the solution to poverty, inequality and corruption in this sector is to empower coffee growers to be able to question, doubt, debate; and in this way no one will ever cheat them again. But how long will it take to make this happen? We don't know, but we're sure it won't be fast neither easy.

We can help to begin to make this change by highlighting traceability even more; "Shouting out loud" the name of those cooperatives that are doing a good job; Generating more direct relationships; And asking the key question, how much are coffee farmers receiving per Kg of cherry? An optimum in Kenya is KSH100/Kg of cherry, that is, USD1 per Kg of cherry.

​Suppose we are going to process the lot A, which will be separated according to a series of characteristics that in the industry we call traceability (origin, altitude, process, cultivation, fermentation, etc.); The quality of lot A will be defined by the way in which its cherries are harvested. After the harvest, there will be no possibility of increasing the quality of this lot, we can only maintain it and try very hard not to reduce it.

​Today, we often hear about processes with different types of experimental fermentations, which tend to confuse the expectations of our customers, and we may forget that coffee is the result of the sum of many factors and circumstances, which go beyond one or another specific fermentation.

​In Kilimanjaro Specialty Coffees we find it very positive that producers and importers continue experimenting with processes and fermentations that allow the development of the industry; but we also hope that these flashy names are not used to influence a purchase decision, or as a tool to charge more for a lot that perhaps was not harvested the right way, and it is assumed that just by having a "funky" fermentation the lot will develop a certain flavor, sweetness or quality. This is important, since otherwise we would be replicating the model followed in Indonesia with the Kopi Luwak, where due to the wonders of nature and the well developed nose of the civet, when in freedom, it was able to select the cherries with the greater amount of sugars (selective picking), and the quality of the coffee was given in the first place for this reason and not only by "intraintestinal" fermentation. Then we all know what happened to the sadly famous Kopi Luwak.

​For this reason, it is essential for us to travel every year to origin in harvest time, and observe first hand the standards that will dictate the quality of the lots that we will bring to Barcelona.

Enjoy your coffee and remember that quality is the result of the sum of many factors and not just one of them.

​But how has this happened? How can such an underestimated and undervalued origin by the world of specialty coffee, can become a new quality trend in many countries, and a No. 1 favourite for many coffee enthusiasts around the world in such a short time?

We believe that the answer to these questions is based on three fundamental changes that Sumatran producers understood, adopted and were willing to work very hard to achieve.

1.- Low price of coffee: We all want to live well, we all have bills to pay and we all want to give our children a good education. Sumatran coffee growers are no exception to that, and they understood that the key to improving their quality of life was to concentrate on producing high quality lots in order to obtain better prices. The only way that "C" prices would work in real life, it would be for a large estate, with many hectares of land and with large volumes of production. For small coffee farmers who own less than one hectare of cultivated land, the focus must be on high quality coffee and intercropping.

​2.- Traceability: today in Sumatra, it is not uncommon to find small cooperatives dedicated to producing traditionally cultivated coffees, in a specific area, with a determined variety and produced by a small and identifiable group of people. The lots are fully traceable, to a small village or a small group of coffee growers. This reality responds to a worldwide demand for quality and reliable information. Unlike before, when most of Sumatra's coffee was sold under the name of "Sumatra Mandheling," when there is no place, call Mandheling in Sumatra.

​Processing methods: There are many producers who are experimenting with different processing methods and fermentations in Sumatra. Although, these are new and powerful tools for them, they are improving and gaining experience quickly. We really hope that very soon we will be able to be buying natural, honeys, wine, and more lots with experimental processing methods, but until today we do not believe that the industry has reached that level yet. But there is one processing method that for us is the King, and until today, we haven’t been able to find any better coming from this exotic island and neither from the whole Indonesian Archipelago. This is Giling Basah! If you don’t know what Giling Basah is, please check our Youtube channel, we have a couple of explanatory videos there, both in English and Spanish. We'll leave the link of our channel in the bio.

Enjoy your Sumatran Coffee, and always remember: DO NOT buy cheap coffee!

​1º THE DENSITY OF THE LOT

During the washing process, there are many more opportunities for selection and grading than in the natural process. Although, lately in origins such as Ethiopia and Burundi, where there are cooperatives focusing on quality, they have begun to introduce hand selection and flotation grading, prior to the drying of the cherries on patios or African beds.

This "lack" of selection and grading during the dry process, generates big differences in the density, moisture content, sugar content and cellular structure of the beans of a certain lot.
​
Therefore, to obtain consistent results during your roasting, it will be necessary to adjust your profile, which should be different from the one you use for high altitude washed coffees, and also different from the one you use for Brazilians naturals, since these beans are less dense than those from Ethiopia or Burundi for example.

​2º METABOLIC EVENTS THAT OCCUR IN THE BEAN DURING DP

During the dry process, a series of important metabolic events occurs within the bean that are almost imperceptible to the human eye, but very much to the taste buds!

In the cell wall structure of the bean, there is a significant mutation of organic and inorganic compounds, a migration of low molecular weight sugars (such as sucrose, glucose and fructose), and a relative (but not absolute) increase of polysaccharides and acetic acid.

​3º PRACTICAL ASPECTS TO CONSIDER

- Start your roast with a lower charge temperature. (25% less than  what you use your high-density washed profile is a good starting point)
- Try to stretch the drying stage, so you can "thermally align" the whole batch.
- Reduce the amount of energy input (with air flow and/or gas) when the crack begins, but without extending its development for more than 1.30 min.

We hope this article become useful and let us know in the comments what is your experience roasting natural coffees from Ethiopia or Burundi!

From a botanical point of view, the definition of an heirloom variety establishes that this must be open-pollinated. Arabica coffee is a self-pollinated crop, so from the very beginning the definition of heirloom doesn’t apply to Arabica coffee.

For many years in the coffee industry, the word Heirloom has been used as a generic term to describe one or a group of unknown cultivated varieties in a particular lot, farm or region, that over a long period of time has been planted and passed from a coffee farmer to the next.

​Since the Specialty Coffee movement started to rise in western countries, there was an obvious necessity for traceability and more information. Although the Jimma Agricultural Research Center (JARC), has been working since the 70’s in researching and developing new varieties, at the time, importers had very little information to describe the varieties of the coffees they were buying from Ethiopia.

Today, thanks to scientists such as Getu Bekele, who have been studying Ethiopian wild and cultivated varieties for decades, we can learn, recognize and differentiate, two big groups of Ethiopian Coffee Varieties: the Regional Landraces and the JARC improved.

​There are between 6.000 to 10.000 Regional Landraces and the JARC has developed around 40 improved varieties, which has been distributed among farmers all over the country. These improved varieties address issues of CBD, leaf rust, cup quality and yielding, and today, are widely used all over the coffee growing regions in Ethiopia.

For example, if we analyzed the Jimma Region, we can learn that the improved varieties of the area belong to the Metu Bishari Selection of 1974/75 including: 74110, 74112, 74140, 74148 & 74165 varieties. The Regional Landraces found in this area will include: Kuburi, Bedessa, Yawan and Dalacha among others.

Also, there will be a specific and different set of improved varieties and Regional Landraces found in Yirgachefe/Sidamo, Harar, Gera and Walaga.

If you want to know more about this very interesting topic, check Getu’s book, “A Reference Guide to Ethiopian Coffee Varieties”.

And last but not least, enjoy your Ethiopian Coffee with full traceability 😊

​In August of the year 2018, the price of coffee reached levels considered alarming by the majority of those who work in the coffee industry. For the first time in 12 years, the "C" price in New York fell below 100cts/lb. While it is true, the average price of the last 12 years is not much higher than 120cts/lb, this decline generated unprecedented reactions in the specialty coffee world, which we think is positive.

Historically, the price of coffee has been extremely volatile, due to the never ending discrepancies between supply and demand. But these constant cycles of highs and lows, have devastating effects for producers and coffee workers from around the world. Of course, in the United States this crisis goes virtually unnoticed, where the global coffee market is dominated by few multinationals: Kraft General Foods, Nestle, Procter & Gamble, Sara Lee, J.M. Smucker Company, Starbucks Corporation and Dunkin’ Donuts. 

Globally, coffee is a US $ 100 billion business annually (Business Insider 2018), but producing countries only capture US $ 20 billion of this value, with most of the profits being retained in developed countries. As on the supply side, the coffee world is very fragmented, with millions of small-scale coffee farmers, the power of the business lies in the large importers and roasters, who buy the green beans and process them into various products.

But what would happen: if small coffee farmers knew exactly how much their product is worth? If they could calculate their production, logistics and marketing costs? And if they could obtain a price that promotes the quality and sustainability of their production?

​We strongly believe that the key to unlock this crisis, does not lie on the same companies that have controlled the business for centuries, but it is at the origin. It should not be New York, London or Berlin, who decides what is the "fair price" that a coffee farmer must obtain. But it must be the coffee farmer, informed and empowered, who demand the price that he deems appropriate, according to the quality he obtained and the investment he made.

We have an invaluable opportunity in the young and new generations of coffee growers, with unlimited access to online information, eager to learn and with a global mind set. There is where we must aim all our efforts to improve  this reality.

Let's make this a sustainable business for everyone and enjoy your specialty coffee!

​On our last trip to Kenya we met the great "Dr. James", who works at the "Kenya Coffee Research Institute" station in Nyeri. In this place, he explained, how they are performing grafting of Ruiru 11 with SL 28, and the importance of its result for the future of the industry.

Grafting in Agriculture, is a technique where tissues of different plants are joined to continue their growth together. This technique seeks to obtain the best of each of the varieties. Generally in plant breeding, the greater the genetic distance between the two parents, the more "vigorous" the child will be (World Coffee Research).

​Ruiru 11 is a variety of high productivity and resistance to diseases. But the problem is that its root is too short, and it is not able to get enough nutrients from the rich African soil. This usually causes poor results in the cup, without the usual complexity of other varieties grown in Kenya.

In contrast, SL 28, is a variety, which as we all know, has an excellent cup quality, but it has low productivity and is susceptible to diseases such as Leaf Rust or CBD.

Dr. James and his team are grafting leaves of Ruiru11 (scion) with a root of SL 28 (stock), to create resistant varieties of high productivity, with the capacity to absorb more nutrients and hopefully, obtain a better quality in the cup .

​It is urgent that we begin to work together towards the development of new varieties and the increment the genetic diversity of this specie that we like so much.

Enjoy the genetic and organoleptic diversity of your Kenyan coffee!