Coffee processing is an important step in the production of coffee. There are various methods that can be used, each with their own benefits and drawbacks.
The semi washed coffee process is a hybrid of the dry and wet methods. It combines the benefits of both while minimizing the drawbacks.
In this article, we'll take a closer look at the semi washed coffee process and how it compares to other processing methods.
History
The semi washed coffee processing method was first developed in Brazil in the 1970s. It was created as a way to improve the quality of coffee while reducing the cost of production.
The semi washed process quickly became popular in Brazil and soon spread to other coffee-producing countries. Today, it is one of the most common processing methods in the world.
The Cherry
The coffee cherry is the fruit of the coffee plant. It contains two seeds, which are known as coffee beans.
The coffee cherry is typically red or yellow when it is ripe and ready for harvest.
The semi washed coffee process begins with the cherries being sorted and cleaned. The coffee cherries need to be free of any debris or foreign objects.
Once the cherries are sorted and cleaned, they are then pulped. The skin of the coffee fruit is removed during the pulping process. The pulp is removed from the coffee beans, leaving them with a thin layer of mucilage.The Mucilage
The coffee beans with their thin layer of mucilage are then fermented.
The mucilage helps to protect the coffee beans during fermentation. This allows for a more controlled and consistent fermentation process.
Unlike the washed process, in the semi washed process the coffee beans are not rinsed after fermentation. This means that there is still a small amount of mucilage present on the beans.
This fermentation process breaks down the mucilage and makes it easier to remove. In the Semi Washed process, the mucilage is only fermented for 12-18 hours. This is shorter than the fermentation time for the Wet Process, which can be up to 48 hours.
Fermentation
During fermentation, the coffee beans are kept moist. This can be done by soaking them in water or by using a humid environment.
The fermentation process with the semi washed method takes place in tanks. The coffee beans are constantly stirred to ensure that they are evenly fermented.
After 12-18 hours, the coffee beans are then washed. This removes the remaining mucilage from the beans.
With Semi Washed coffee, there is less chance of over fermentation, which can lead to an unpleasant taste. This method of coffee processing is said to produce a cup of coffee with a more complex flavor.
Honey Process or Wet Hulled
The final step in the semi washed coffee process is known as the honey process or, alternatively the wet hulled process. These are two different processed that yield different types of semi washed coffee, and they differ in how they treat the coffee fruit just before drying.
The wet hulled process is often used in Indonesia and parts of Central America. In this method the hull is removed at a greater moisture level, requiring a special machine called a huller. The coffee beans are then sun dried to a lower moisture content.
The honey process is used in countries such as Ethiopia and Costa Rica. In this process, the coffee beans are dried with their mucilage still intact.
This gives the coffee a sweeter taste as the sugars from the mucilage are absorbed by the beans.
The honey process is a more difficult and costly method as it requires more labor and time.
Drying
The coffee beans are then dried, typically in the sun or in mechanical dryers.
Drying is an important step in the coffee processing as it removes any remaining water from the beans.
This is important as too much moisture can lead to the beans going moldy. Semi Washed coffee typically has a moisture content of around 12%.
Once the coffee beans are dried, they are then hulled. This removes the parchment from the coffee beans. Semi Washed coffee typically has a parchment content of around 0.5%.
Benefits
The coffee cherry’s protective layers can mask the true flavor potential of the bean.
The goal of the semi-washed process is to remove as much of the fruit as possible while still maintaining some of the mucilage.
This results in a coffee with more clarity and brightness than a fully washed coffee, but with more body and sweetness than a natural coffee.
Another benefit of the semi-washed process is that it is less labor intensive than the fully washed process, making it a more economical option for coffee producers.
Drawbacks
The main drawback of the semi washed process is that it can be difficult to control.
Because the coffee beans are only partially removed from the fruit, they can still contain a lot of the fruit's natural sugars. This can lead to coffee that is too sweet or even fermented tasting.
Additionally, because the beans are only partially dried, they can be more susceptible to mold and other defects.
Overall, the semi washed process can produce some great tasting coffee, but it is important to be aware of the potential drawbacks.
Roasting
When roasting semi washed coffee beans, it's important to maintain a consistent roast throughout the batch. This can be difficult, as coffee beans absorb heat differently depending on their size and moisture content.
Semi washed coffee beans should be roasted at a lower temperature than fully washed beans, and for a shorter period of time. This allows the beans to retain some of their natural oils, which gives the coffee a more robust flavor.
The process is often used for coffees that are going to be roasted dark. This is because the beans can withstand the higher temperatures without becoming bitter or charred tasting.
Generally speaking, coffee roasters feel that semi washed coffee beans are more difficult to work with, but the end result is a more flavorful cup of coffee.
Impact on Flavor
The semi washed coffee process results in a coffee that has a cleaner taste than the wet process. This is because there is less of the fruity flavors present in the coffee.
The semi washed process also results in a coffee that has more body and a richer flavor than the dry process. This is because the coffee beans are not fully dried, so they retain more of their natural oils.
Common flavor notes associated with semi washed coffee include: chocolate, caramel, spice, and nuts.
Where is the Semi-Washed Process Most Used?
This method of processing coffee is most common in Central and South America. This is because the climate is well suited to drying coffee beans, and the semi washed process is less labor intensive than the fully washed process.
In recent years, the semi washed process has become more popular in Ethiopia. This is due to the fact that Ethiopian coffee beans have a natural sweetness that is enhanced by the semi washed process.
How to Prepare Semi-Washed Coffee
When brewing semi washed coffee, it's important to use a light to medium roast. This will help to bring out the coffee's natural flavors and avoid any bitterness.
It's also important to use fresh, filtered water when brewing semi washed coffee. This will help to ensure that the coffee doesn't taste sour or off.
When brewing semi washed coffee, it's best to use a pour over or drip method. This will allow the coffee to slowly extract, which will help to bring out its full flavor potential.
FAQ
What is semi washed coffee?
Semi washed coffee is a type of coffee that has undergone a partial wet processing method. This means that the coffee cherries are first pulped and then dried, before being hulled and polished. However, unlike washed coffee, the coffee beans are not fully soaked in water. Instead they are only rinsed.
How does semi washed coffee processing affect the taste of coffee?
The main difference between semi washed coffee and washed coffee is that the former has a higher density of sugars. This results in a sweeter cup of coffee with more body. Semi washed coffee also has a higher acidity level than washed coffee.
How does semi washed coffee compare to other processing methods?
In general, semi washed coffee falls somewhere in between washed coffee and natural coffee. It has more body than washed coffee but is less intense than natural coffee. Semi washed coffee is also less sweet than natural coffee but more sweet than washed coffee.
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