Coffee processing methods of the world’s top gourmet coffees is achieved by many different methods. These processing techniques can be grouped into four categories: Wet Processing (Washed), Dry Processing (Natural, Sun Dried), Pulped Natural Processing, and Semi-Washed Processing.
Farmers choose the processing method best suited for their climate and capabilities – whether they have a long, dry season to allow for dry processing, or ample water supply because of a high tropical environmental, and how much labor they have access to.
Here’s a quick guide of all of these coffee processing methods, with detailed explanations linked out.
- Wet Processing involves washing the coffee beans of fruity material while the beans are still moist right after they are picked.
- Dry Processing involves first drying the coffee cherry in the sun while regularly raking the beans free of any dried fruit.
- Pulped Natural Processing involves initially pulping the coffee but without a fermentation stage as in Wet Processing, then drying the beans with much of the mucilage still attached.
- Semi-Washed Processing method a demucilaging machine is used to remove the coffee cherry’s skin and most of the mucilage.
- Aquapulp is another method which cleans the coffee cherry initially and has recently been adopted by many areas that formerly used wet processing.
Washed / Wet Processing
The washed processing method involves soaking the coffee cherries and allowing fermentation to take place to separate the cherry from the bean – or it can be run through a mechanical depulper to remove the coffee cherries. Once the green coffees are removed, they’re washed once again to remove residue and placed outside to dry on a patio or raised beds.
The flavor of the resulting coffee is more “pure” than other methods – unaffected by the coffee cherry.
Dry Processed / Natural / Sun Dried
Naturally processed coffees are dried with the coffee cherry still around the coffee bean, without any removal, allowing time for the natural flavors of the coffee cherry to be imparted onto the coffee itself.
Dry processed coffees tend to not have a huge range of flavor, because the flavor is always pushed towards fruity and sweet due to the coffee cherry. Dry processing is especially prominent for coffees from Brazil, Ethiopia and Yemen.
Pulped Natural / Semi Dry / Honey Process
The pulped natural or “semi dry” process involves removing varying portions of the coffee cherry – it is somewhere between Wet Processing and Dry processing. Recently, these varying levels have become known as “black honey”, “red honey” and “yellow honey” respectively – more of the coffee cherry left on the outside results in more caramelizing and a darker color. Conversely, less coffee cherry means less sweetness and a lighter color.
Wet Hulled / Semi Washed
With this method, coffees are pulped at the farm to strip the coffees down to parchment and mucilage, then sent to be processed at the processing facility. This is also known as “Giling Basah” (wet grinding) in Indonesian countries.
The processing methodology is typically passed down through generations within a country, with current farmers doing things fairly similar to what their fathers and grandfathers and so on did. Government organizations and international coffee organizations sometimes step in to provide alternate methods or share their techniques, which helps raise the standards across the industry.
Some methods are simply unavailable or too costly however – in areas where water is scarce or equipment unavailable, the processors may be limited in their options. While it’s difficult to imagine in first world countries like Canada, the United States, United Kingdom and Australia, much of the coffee growing world is limited by a lack of knowledge as well as unavailability of basic equipment.
Espresso and Coffee Brewing Tips
How a coffee is processed does have some affect on how a coffee is roasted, and master roasters use this information to tweak their roast profile.
For tips on brewing the perfect cup of coffee see the Espresso Coffee Guide’s section on Coffee Brewing. For detailed definitions of coffee terminology see the Coffee Terms. You can also read detailed specialty coffee flavor profiles see Gourmet Coffees and Espresso Drink Recipes.
Also check out the evolution of coffee and espresso recounted in detail in our World’s Best History of Coffee.