Wet Hulled Coffee Processing

Coffee bag and mug with saucer on table.

Have you ever heard of Giling Basah coffee? What about Mandheling? Wet Hulled? These are all terms used to commonly denote a very specific, unique form of coffee processing, that results in a full-bodied, bold cup of coffee. While this process can take place anywhere, it has become synonymous with the Indonesian island of Sumatra (Manhaling is actually a region on Sumatra, but has become so closely linked with the process, it has become shorthand). As May’s Roaster’s Choice is featuring one of these Sumatran Wet Hulled coffees, this seems like a good time to go over this fascinating process!


First, a quick refresher on typical washed coffee processing: the fruit of the coffee plant is taken and run through a machine which separates the pulp from the seed (bean), the coffee is then submerged in water for (typically) 12-48 hrs, after which it is laid in the sun to dry, commonly for 10-20 days. After washing the coffee, the beans are still covered in a protective layer, called the endocarp. As it dries, this layer becomes papery and is called parchment, which the coffee is stored in until it is time to ship. It is surrounding this parchment layer, where the wet hulled process differs.


Instead of letting the coffee dry in the endocarp layer, the coffee is dried only for a single day, then run through a machine that removes the parchment. The coffee is then put back out to dry, taking a shorter period to dry, with the beans no longer having the protective coating. This leaves the beans a dark blue-ish color and imparts on the coffee a more intense, robust flavor, perfect for coffee drinkers who like a bold, strong cup of coffee. For example, we noticed potent notes of cedar and dark roasted cacao nibs in our Sumantran.


Coffee is undeniably versatile and widely varied. It is a plant that can vary based on a wide range of factors such as variety, location, climate and a whole host of other natural factors. With the Wet Hulled process, however, we can see how people can impart their own stamp on the coffee in the production process through unique and innovative techniques. We are excited to share another example of the many ways coffee can be enjoyed!


Want to try a Wet Hulled coffee? Check out this month's exclusive Roaster's Choice offering, Sumatra Tano Batak.