Green Coffee Process

Once the preferably ripe coffee cherries are picked – they need to be processed and the sooner this gets done the better for the quality of the green processed coffee.

There are two predominant methods that coffee is processed with a whole host of methods in between as well as newer methods being introduced. The two predominant methods are Natural and Washed.

Natural processing is when the coffee is dried with all the fruit attached to the bean. It is laid on beds to be dried naturally and is turned regularly to avoid the growth of molds and ensure a more even drying process. This method is usually employed where there is a scarcity of water such as in Ethiopia. Once the coffee cherry has dried to a sufficient level around 12% moisture content the dried cherry is removed to present the dried green coffee bean. Most natural processed coffees have more fruity flavors and are usually sweeter and fuller-bodied.

Washed coffee is normally used in areas with more readily available sources of water such as Guatemala where we source our products from. Once the cherries are picked the skins and flesh are removed which is commonly referred to as de-pulping and the skin and the beans are separated. The beans are then left to ferment over a period of about 12 – 24 hours. The fermentation is an important step as it imparts flavors to the bean and over-fermenting can affect the taste negatively. After the fermentation, the beans are washed to remove any of the mucilage that may have remained after de-pulping and then the beans are laid on raised beds or patios to be dried with the parchment layer still attached to the bean. Washed coffees tend to be cleaner tasting than other processing methods. This is because the removal of the cherry allows the inherent, natural characteristics of the coffee to shine through.

Honey Processing could be considered a combination of washed and natural process as the coffee is depulped and then set to dry leaving some of the flesh and mucilage on the beans. This creates a sticky outer layer on the bean as it dries hence the reason it is known as honey processing. There are different types of honey processing – including black, yellow, red, pink, and white. These colors are indicative of how much flesh and mucilage is left on the coffee as it dries. 

There are also a few experimental processing methods that have been introduced, such as Aerobic and Anaerobic Fermentation, Carbonic Maceration, Lactic Fermentation and Double Fermentation. These are usually more complex than traditional techniques, as they involve more variables and require farmers to exert more control over the process.

Aerobic and Anaerobic Fermentation are two types of cellular respiration involved in the production of energy from glucose. Aerobic fermentation is usually a shorter and more intense process than anaerobic fermentation, because there is no exposure to oxygen with anaerobic fermentation, microorganisms break down the sugars at a much slower rate – which allows for more complex flavors to develop.

Carbonic Maceration is similar to Anaerobic Fermentation however the tanks are flushed with carbon dioxide. The fermentation occurs in a closed sealed container and the carbon dioxide is used to flush out the oxygen. This is a process that is used in some wine making techniques.

Lactic Fermentation is a technique similar to those used for other fermented food products (such as sourdough bread and sauerkraut). With lactic fermented coffee, producers add lactic acid cultures to the coffee as it ferments.

Double Fermentation also can be known as Double Washed is where the coffee beans are fermented and washed and then the process is repeated leading to a brighter and cleaner tasting coffee, as higher levels of mucilage are removed. This is a technique commonly used in Kenya, however it does lead to higher processing costs.

The coffee that our growers produce in Guatemala goes through the age-old process of a single ferment and wash. Guatemala still produces some of the best coffee in the world. If you have tried our coffee then you will know the truth of this statement.

Thank you for supporting Inn Kapeu “Great Coffee – With a Mission”