Natural, Washed and Honey Coffee Processing Methods
Processing coffee is nothing but removing the bean from the coffee cherry, which is a must before roasting. Like any other pitted fruit, coffee cherries have mucilage around the seed, pulp and skin.
There are different methods to remove the seed from that cherry, which in turn affects the seed's/beans flavour. 3 coffee processing methods are most popular today: Natural (also called dry process), Washed (called wet process), and Honey (called pulped natural).
Natural Processing Method
This is the oldest and most traditional way of coffee processing which originated in Ethiopia. It involves drying out the whole freshly picked cherry. The cherries are harvested once ripe and then spread out on raised drying beds or patios in thin layers to dry under the sun. Over the next 3-6 weeks, the farmers will rake these cherries and rotate them to slow down the fermentation and prevent spoilage. During this time, the sugars and mucilage will latch onto the seeds, which develops its flavours and makes them sweeter. After the cherries have been completely dried they’re sent to mills for hulling. This is basically the separation of the seeds from the rest of the dried fruit. The next is dry milling, where they remove the seed’s skin. The beans and then stored and shipped.
Natura processed coffees, have a heavy body, and complex tasting notes, since the beans dry with the full cherry. Inconsistencies in fermentation also make these difficult to replicate. Moreover, these coffees can also be some of the sweetest you'll ever taste. The final coffee will have brighter, fruitier flavors.
Washed Processing Method
Washed processed coffees are also called wet processed. Here one removes the fruit entirely from the bean before drying. Machines called de-pulpers remove the seeds from the cherries before drying them. The ripe cherries are thrown into a de-pulping machine, where the outer parts are removed and only the seeds come out.
The coffee seeds are then left in a water tank for about 18-24 hours to ferment. During fermentation, microorganisms in the seeds create enzymes that break down the seeds’ mucilage. Once fermentation is complete, the seeds are taken out, and washed to remove any remaining flesh, and then they are left to dry similar to the natural processing method. They are dried under the sun or by using mechanical dryers.
This processing method is more bean focused and the final flavour comes directly from the sugars and nutrients that the bean retains while the cherry is growing. Because of this, the soil quality, plant nutrition, temperature, sunlight etc play important roles. This process brings out the true qualities of the bean and is more consistent. Washed processed coffees, have cleaner, more crisp tasting notes and a lighter body in comparison to natural processed. Our single-origin Nicaragua coffee and Mysore Nuggets are processed using the washed method.
This method is somewhere between natural and washed. It derives it’s name from the sticky texture of the bean once it has been processed. The skin of the coffee cherry is removed, but the mucilage (the sticky part) is partly left.
Honey process or pulped natural is a method in which the ripe coffee cherries are de-pulped, but allowed to dry without washing (it bypasses the fermentation stage of the wet processing). There is still some fruit present on the bean, but not as much as in the natural process. The more flesh or mucilage left on the bean, the sweeter and fruitier the final cup is likely to be. As coffee cherries dry, their sticky outer coating oxidizes and darkens.
The amount of mucilage removed varies in this method, so coffees were generally described by their drying colour - white, yellow, red, and black processed. Coffees with more mucilage removed dry more quickly and are lighter in color. Coffees with less mucilage removed dry slower and are darker in colour. After the green beans are fully dried, the remaining mucilage is removed, and the beans are ready for storage and shipping.
In contrast to washed beans, honey-processed beans have a lovely sweetness and aromatic notes. But they also display clean flavours and brightness that natural processed coffees miss. With Honey Processed, you get the best of both, natural and washed methods.
Hoping that this blog has given you a better understanding of the different ways coffee beans are processed.