The world of coffee is vast. The variations are endless. You can brew your coffee in a variety of ways. All roasters roast in their own special way. And the raw material itself, the coffee beans, not only grow in different places – they are also prepared using different methods. All the parameters (brewing, roasting, process) and the care with which the work is carried out affect the final result. Here we go through the most common preparation processes and tell you more about how they leave their mark on your cup.
Coffee is a fruit! In English they are called cherries or berries, and we call them berries. They flower, are caressed by the sun’s rays, with cooling winds, pouring rain and about six months later – when they have turned red (sometimes yellow or yellow-red) in color, they are harvested. Inside the berries you’ll find the bean, which is almost always made up of two small seeds and it’s these that we roast after they’ve dried. But before we get that far, we need to remove the shell, the jelly-like flesh and finally the thin film called pergamino closest to the bean. Different methods are used for this. Let’s start with the original one.
Conditions are different in different parts of the world. Some coffee-producing nations have plenty of water, others do not. However, although water availability is a factor to be taken into account, it does not necessarily determine whether the interior of the coffee berry is revealed by washing away the skin and pulp or whether, as in this method, the coffee bean is allowed to dry out. With the berry-dried method, you get an incredibly flavorful coffee and, skillfully executed, they are truly special. But how does it work in practice?
Immediately after harvest, the berries are sorted. Only fully ripe berries can start the process, and those accidentally picked slightly too early are set aside or processed in another way. The berries are then laid out on woven drying mats, large drying tables or – most commonly – on concrete blocks on the ground.
After the berries have been laid out to dry, the coffee farmer’s job begins, which requires patience. At all costs, moisture and mold infestation must be avoided throughout the drying process, which takes two to six weeks depending on the climate. It is a constant turning, with shovel and rake. Sometimes fans are used to speed up the process.
The time it takes for the mucilage to dry instead of being washed away (as with the wet method, more later) is what makes the two methods significantly different in the end. Because during the drying process, the mucilage ferments with the help of natural yeast in the air. This affects both the sugars in the mucilage and the acids. Fermentation penetrates the beans and definitely leaves its mark on the finished coffee. These are the qualities that producers in countries with good access to water strive for anyway, they are that great!
The balancing act is precise. If drying takes too long, the bean can crack and dry out. If it goes too fast, the bean risks turning sour. Moreover, conditions change from day to day in most countries and the craftsmanship of the farmer is reflected in the end result.
The beans are considered to be fully dried when their moisture content is 11%. The berries have then become a little raisin-like and now the mucilage must be removed. This is known as ‘punching’ the coffee and different tools are used for this. The important thing is not to damage the beans.
After the mucilage is removed, the coffee beans are polished, again a labor-intensive but important job. A final sorting takes place and the beans are bagged for transportation to the roasters.
As in the case of dried coffee, the bags leave the producer after being polished and sorted. The path to this stage, however, differs significantly in several different steps.
Today, the wet method is by far the most common method of processing freshly harvested coffee. This is not only because it is easier to control, but also because it provides a cleaner and more origin-specific profile. While there are certainly smart ways to minimize water use here, the process requires good access to fresh and clean water. Similarly, the wet method requires greater investment on the farm.
In the wet method, the mucilage is removed by placing the freshly harvested berries in water. At the same time, a first sorting takes place: the ripe berries of good quality sink to the bottom. The damaged, unripe berries float to the surface.
In the next step, the berries are washed so that the flesh falls off. In English, they are called ‘depulpas’. Metal disks move the berries back and forth. This removes most of the pulp and skin, but to get the beans completely clean, they must be left in water for a short time. For just under 24 hours, fermentation takes place and the starch in the mucilage is broken down by enzymes. If you want the purest flavor, change the water to remove the mucilage faster.
The whole process here has taken about 4 days. Now it’s time for the beans to dry and, as with all other methods, the pergamino skin must be polished off, the coffee sorted one last time, before the coffee is ready to be sent to us in Tyresö.
Specialty coffee is great because we’re constantly striving to further refine the taste of coffee. There is a lot of ingenuity and many pioneers.
In Costa Rica, a cross between the wet and dry method was born in 2009. The country had just suffered a major earthquake, which led to water rationing. Oscar and Fransisca Chacon were forced to find a creative solution, and became the originators of the now popular honey process.
Using less water than the wet method, the honey process pulped the shell off the bean, but left some of the mucilage behind. The beans are then laid out on beds and in the shade, the remaining sugar compounds penetrate the bean and give rise to deliciously sweet flavors and aromas. Depending on how much of the mucilage is left after pulping, the varieties are named differently. In yellow honey, about 60% of the mucilage is removed before the beans dry. In the case of black honey, all mucilage has been left behind. In between we find white, gold and red honey.
Great skill is required to achieve a perfect honey process because, as with the dry process, the berries must neither be dried too hard in the sun nor become moist at the bottom and thus require constant turning.
Another method is Indonesian Giling Basah. This starts with the wet process, but instead of letting the coffee dry down to 10-12% humidity, which takes several weeks, before the pergamino skin is polished off and the coffee can be packed in bags for further transportation, here you only wait until the coffee’s humidity is 25-35% before the pergamino skin is removed. The result with Giling Basah is a completely different coffee – earthier, herbier and with tobacco notes.
A final process worth highlighting in this context is anaerobic fermentation. Although it hasn’t taken hold yet, it may well take off in the same way that honey has in recent years – 10 years after pioneers Chacon introduced the method.
Impressions from the wine world are vast. Washed coffee beans are left to ferment in a low oxygen environment, inside well-sealed vessels. This process takes place over a short period of time, usually 1-3 days. A natural carbon dioxide pressure is formed, and the aromas of the mucilage are thus more easily absorbed by the beans and can leave an even greater mark on the coffee than would have happened in a honey or natural process.
The method is new and untested. The results are mixed to say the least. But we at White Elk Coffee believe that the producer who cracks the code, with enough willingness to experiment, can become one of the brightest stars in the specialty coffee sky for a long time to come.
Published by Fredrik Gustafsson, 21-04-20
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