Discover how coffee gets made and what it does to the taste of your daily cup.
Like tea, wine, and even beer, coffee starts with a fresh product. Wine has its grapes, beer with its hops, and tea by the leaves. Coffee begins the same way; the cup of coffee you drink every day is actually a product of coffee cherries. The beans you buy are the roasted seeds of those cherries! However, many steps go into sourcing and pulling that seed from the cherry. How (much of) that cherry gets removed directly affects how your coffee will taste. We explore four different coffee processing methods, and how these methods make your final brewed coffee taste the way it does.
What does coffee processing mean?
Coffee processing refers to the way that a seed is removed from a coffee cherry. Like any other pitted fruit, coffee cherries have a seed, the pulp, the mucilage around the seed, and a protective skin. There are various methods to remove the seed from that cherry, and these methods affect the seed's flavor as it gets roasted and turned into a coffee bean—this flavor sticks around till the final brew.
There are four different ways to process coffee, all of which change the sweetness, body, and acidity of brewed coffee. These methods are called natural process, washed process, wet hulled, and honey processed.
Natural Processed Coffee
A natural processed coffee, also referred to as dry processed, is a traditional yet common way to process coffee today. Originating in Ethiopia, it involves drying out the entire freshly picked coffee cherry with the seed still inside. To do this, coffee producers take all of the cherries and place them on drying beds in the sun. These beds either consist of patios or raised drying tables.
Throughout the course of 3-6 weeks, the coffees will ferment, as producers rake these cherries and rotate them to prevent spoiling. During this time, the sugars and mucilage (that sticky substance that coats the seed) will latch onto the seeds, which develop flavors and make them sweeter. Once the coffee is dry, a machine separates the pulp and the skin from the seed.
Natural coffees result in heavy bodied cups of coffee, with deeper and complex tasting notes due to that time spent developing extra flavors. This development comes from the way that the seeds ferment differently, since they dry with the full cherry still intact. Natural processed coffees can be difficult to replicate because of the inconsistencies in fermentation. Raking coffees by hand can change how often certain cherries are rotating in the fermentation period, and can get moldy if not cared for properly. However, when done right, these coffees can also be some of the sweetest you'll ever taste. A natural processed coffee is juicy, syrupy, and well worth the extra effort.
Unlike natural or dry processed coffees, washed processed coffees are called the opposite—wet processed! In this scenario, machines called depulpers remove the seeds from the cherries before drying them. However, it is not just any cherry that gets seed removal. These cherries must have the perfect amount of ripeness to make sure they are sweet enough, and go through a sorter for density. Once these depulpers remove the skin and pulp from the seeds, the seeds go into tanks full of water. The water ultimately washes the rest of the mucilage and fruit caked onto the seed. Finally, the seeds go onto beds in the sun to dry out.
The washed method, although quick and efficient, can be considered environmentally wasteful. A massive amount of water goes into the tanks that remove the mucilage, and washing stations themselves generate tons of solid waste. These washing stations themselves take an incredible amount of infrastructure, technology, and energy that could be costly to many to operate. However, if the water in these tanks can be reused (typically by rebalancing. the pH level), then this processing method can work towards environmental friendliness.
Washed processed coffees have cleaner, more crisp tasting notes than natural processed coffees. The body of a brewed washed coffee is lighter. There is typically more brightness as well, because of a cleaner acidity that balances out the sweetness of the coffee. They are still just as fruity as natural coffees, but the flavor notes will be easier to differentiate.
Wet Hulled Coffees
Wet hulled coffee, not to be confused with washed/wet process, can also be called semi-washed coffee. During this processing method, depulping machines remove the seeds from the cherries. However, rather than move to drying beds, the cherries get stored in plastic tanks. The mucilage also remains on the seeds, and much moisture is retained. At this point, the mucilage has created a thick husk that encapsulates the seeds. They then go through a process called hulling to remove it, along with parchment (the dry flakes covering a bean) that surrounds the seeds, and laid out to dry afterwards.
This method is common in Indonesia, for its humid climate can make the drying conditions difficult. Wet hulled allows for more efficient and speedy processing, as the drying time is half of the other processes. The taste of a wet hulled coffee is also heavy bodied thanks to the dried mucilage, but it is also chocolatey, savory, and nutty—perfect for a blended roast.
Honey Processed Coffees
Honey processed coffee is a method that involves a combination of both the natural and washed methods. It is a rare and demanding method, and not as commonly practiced as the previous two. However, it produces a unique cup of coffee, with flavors similar to both of the previously described processing methods. During honey processing, a depulper removes the seed from the cherry before it dries out. However, it does not go into a washing tank to get rid of the mucilage. That mucilage, which is what the honey refers to, stays on the seed as it dries in the sun afterwards. The amount of mucilage left behind determines the sweetness, and there are even machines to control the amount on the seed. The seed then finishes out drying on the bed, and also gets raked and rotated to avoid mold.
The flavor components of honey coffees are varied and complex. Like washed coffees, they have cleaner bodies than natural coffees. Honey processed coffees also have richer notes of syrupy sweetness thanks to the left over mucilage. There is more pronounced acidity as well, but more mellow than washed processed coffees. We go into even more detail on honey coffees here (i.e. what's the difference between black honey and red honey?).
When buying your next bag of beans, pay attention to the processing method, which you can usually find labeled on that bag. You may find yourself curious to learn how each method will alter and improve your final brew!
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