Why is coffee sometimes washed and what does the term "natural" on the label of your favorite coffee tell you?
Long before roasting, the first important steps for the later taste experience of your favorite coffee are taken directly after harvesting. The two most natural processing methods used by coffee farmers to produce specialty coffee are washing the coffee "washed" or drying it in its coffee skin "natural".
In order to stop the natural fermentation processes, wet-processed "washed" specialty coffees are separated from their soft skin and their mucilage is removed after harvesting.
Mucilage is a jelly-like layer within the coffee fruit that covers the coffee bean and its silver skin, the so-called parchment. It consists largely of sugar, and if it were not removed after harvesting, it would initiate a fermentation process that is not desired in the "washed" process at this point.
Steps in washing specialty coffee:
- Mechanical removal of the pulp.
- 8 - 16 hours of storage in tanks, during which time the attached mucilage should have separated from the bean.
- Multiple washing of the coffee beans under clear water. During this process, it is important to completely remove the previously dissolved mucilage in order to stop the fermentation process.
- Coffee beans are laid out on sun beds to dry.
By removing all the pulp before drying, the bean's original aromas are unadulterated and fully revealed. Washed coffees are appreciated for their clean and authentic notes.
Unlike washed coffee, the coffee bean is not removed from the fruit before the drying process, but is dried as a whole.
This process is often very time-consuming. This is because the constantly changing weather conditions that exist in most coffee-growing regions make the drying process difficult. To avoid mold, the coffee is therefore spread out in a sunny place immediately after harvesting and turned by hand several times a day in the initial phase. Errors in the drying process can lead to defects in the coffee bean and unpleasant aromas after roasting.
When done correctly, "natural" processed specialty coffees usually offer more fruit and fermentation flavors. The coffee bean has more time to interact with natural sugars in the coffee fruit while enzymes break down the mucilage around the bean.