From Sweet Maria’s travelogues , here are a set of images of how coffee wet processing is performed.
Wet-processing is still the preferred way to take arabicaArabica refers to Coffea Arabica, the taxonomic species name of the genus responsible for around 75% of the worlds commercial coffee crop.: Arabica refers to Coffea Arabica, the... ...morecoffee cherryOriginally coffee literature referred to the fruit of the tree as a "berry" but in time it became a cherry. It is of course neither. Nor is the... ...more from the fruit to the bean / seed. Why is that? Let’s look at the history a bit and talk about “natural” processingThe removal of the cherry and parchment from the coffee seed.: Coffee is either wet-processed (also called washed or wet-milled) or dry-processed (also called wild, natural or natural... ...more first.
Dry Process versus Wet Process
Traditionally dry-processing was used in areas with no access to water, or areas where less care was put into the coffee due to low value. Dry-processing required less infrastructure, and was technically easy.
It made sense in areas with extended collector systems, where coffee was gathered in very small amounts from many farmers, the good blended with the bad. It was typically a rusticA general characterization of pleasantly "natural" flavors, less sophisticated and less refined, but appealing. : What is Rustic? This is a general term we came up with... Dried... ...more process that resulted in a rustic tasting cup. It makes sense in that light that dry-process coffee is still called “natural coffee” too.
Dry processing has changed in some ways, and we now have top-grade dry processDry process coffee is a method for taking the fruit from the tree to an exportable green bean. The whole intact coffee cherry is dried in the sun... ...more coffee that requires careful effort to achieve a very intentional result. But in a sense this new wave of dry-processing
The Wet-Processing Advantage
Wet-processed coffee (also called washed coffee) was the traditional path to quality, for the very reason that it was more controlled and a better vehicle to achieve those intentional results: a uniform and clean tasting coffee.
Building a wet millThe wet mill is a processing center where coffee cherry from the tree is brought for initial processing.: The wet mill goes by many names (Beneficio, Factory, Washing... ...more was more of an undertaking: It required land for a central processing station, aka a washing stationIn Rwanda and some other East African countries, a wet mill is called a Washing Station.: In Rwanda and some other East African countries, a wet mill is... ...more, and access to a water source to run the mill and fermentAs an aroma or flavor in coffee, ferment is a defect taste, resulting from bad processing or other factors. Ferment is the sour, often vinegar-like, that results from... ...more the coffee. It required local infrastructure to get the coffee to the mill. It required skilled machine operators for the coffee pulper, and management to track the process. It required hired labor to perform the work, washing the coffee in the channel, delivering it to drying beds or patios etc.
One could make a good argument that the higher quality of good arabica coffee, it’s acidityAcidity is a positive flavor attribute in coffee, also referred to as brightness or liveliness. It adds a brilliance to the cup, whereas low acid coffees can seem... ...more and lower bitterness compared to robustaAteng is a common name for Catimor coffees widely planted in Sumatra and other Indonesia isles.: Ateng, with several subtypes, is a common name for Catimor coffees widely... ...more, could only be revealed with wet-process methods.
And that would be true, except that the care put into dry-processing now, and the costs to do it right, challenge the idea that fine coffee must be washed coffee
History of Coffee Process Systems
The kind of approach and investment, as well as centralization in the wet-process system harkens to colonialism in a sense. Or to the “hacienda” system that was usually owned by a nation’s elites, the landed class. Yet there was nothing intrinsically exploitative about the process. In fact, the systems that did the least to improve lives proved to be those resulting in low-grade commercial coffees, and those might be found more often in collector systems attached to natural coffee production.
As far as defining the process, the steps, the quality of the methods, you can find that repeated over and over in my travel videos, and other travelogues. I will leave it to the photos and captions to underscore the various approaches to creating a fine wet-process coffee! -Thompson
Wet-Process Coffee Method in Photos
The photo set roughly shows the process from coffee delivery and reception at the mill, sortingCoffee is sorted by size, density, and color in its preparation for export.: Sorting refers to several steps performed in the preparation of coffee for export. Coffee is... ...morecherryEither a flavor in the coffee, or referring to the fruit of the coffee tree, which somewhat resembles a red cherry.: Either a flavor in the coffee, or... ...more, pulpingThe first step in processing wet-process coffee, pulp natural or forced demucilage coffees. Pulping simply refers to removing the skins from the coffee fruit, leaving the parchment coffee... ...more off the skin, fermenting the coffee, washing it out of the fermentationA key part of the wet process of coffee fruit is overnight fermentation, to break down the fruit (mucilage) layer that tenaciously clings to the coffee seed, so... ...more tanks, initial sorting while wet, and while drying. All these steps aren’t done everywhere though… and I include a couple photos of pulpers that “machine wash” coffee so that it’s not fermentedAs a defect flavor, a fruit quality in a coffee that is excessively ripe, toward rotten. Fermented flavor can be the result of poor wet-processing, over-ripe cherry, or... ...more, like the PenagosPenagos Hermanos is a Colombian company that produces demucilage coffee processors. This is a forced demucilage machine that uses little water, and removes the coffee fruit layer from... ...more machines.
I hope there is something you noticed about many of these images. I hope you noticed all the labor that goes into quality coffee, how much work it takes, and how we wouldn’t have fine coffee without all those people selecting the fruit, removing defects, washing the coffee etc etc. ! -Thompson