Following collection, the coffee cherry is carried to the mill where it is treated to release the grain. Green beans can be obtained in three different ways: naturally (sun-dried in patios), washed (pulped, fermented, and dried), and semi-washed (pulped and dried). These procedures have been broadened by the introduction of new techniques as a result of the growth of specialty coffee and the demand for novel flavors and experiences. As a result, we learn about cases like Yellow Honey, Wet Hulled, etc.
In the processes that make use of fermentation, this can be done in different ways. The anaerobic that concerns us in this post, is a type of fermentation based on anaerobic processes, that is, those that are carried out without the intervention of air, more specifically oxygen.
WHAT IS IT COMPOSED OF?
It is a chemical reaction to ferment food. The substance decomposes as a result of the interaction of yeasts, bacteria, and other microorganisms. Sugars are often chemicals that degrade. Simply said, fermentation is a natural transformation that happens when sugar and water combine; sugar and water are both present in coffee cherries.
Anaerobic fermentation, as we've seen earlier, needs to take place without the presence of oxygen.
THE WAY IT IS DONE?
To start, thoroughly wash the cherries to get rid of any thorns or contaminants. Depending on the character you want to print on the coffee, you can use either whole cherries in their shells or cherries that have already been pulped. After being cleaned, they are put in oxygen-free, airtight barrels, allowing bacteria to grow that can only exist under these conditions. These bacteria break down and oxidize material while releasing acids and carbon-based components back into the media. Due to this, a conduit with a one-way valve that permits the evacuation of these gases while blocking the entry of air must be enabled.
To determine the duration the grains must be fermenting, which is essential for us to get the most flavor out of the grains, it is required to measure the Ph and take a Brix reading (an indication of the sugar level) before shutting the barrels. Years may pass during the study process before an ideal outcome is reached.
The procedure must be carried out with extreme care, taking into account every small aspect, including cherry selection, cleaning, the proper humidity level, the temperature inside and outside the barrels, etc. Controlling the time is crucial to preventing extra fermentation, which would sour the coffee.
WHAT PURPOSE DOES THIS FERMENTATION SERVE?
With this kind of anaerobic fermentation, it is hoped to improve flavors and provide various coffee profiles. Refine these coffees' sweetness, acidity, and body while also introducing distinctive sensory elements like fruit, caramel, chocolate, and others. These coffees are known for being exceptionally clean and well-balanced in the cup.
The complexity of these coffees also increases similarly. Richer and more intricate sensory details are added.
