Green coffee beans cannot be picked directly from the tree and can be roasted and consumed directly. To have a good flavor, many steps are required. People often think that the flavor of coffee depends on the variety, planting environment and cultivation method, but in fact, there is an important link between planting and roasting, called "coffee bean processing method". What kind of processing method is used generally depends on the local productivity level or the direction of pursuing flavor. If you want to know what common methods are used to process coffee, just follow the footsteps of FrontStreet Coffee and find out~
Processing method = coffee cherries → green coffee beans
If you cut the picked coffee berries crosswise, you can see that from the outside to the inside they are the peel, pulp, pectin layer, parchment, silverskin, and finally the seeds (coffee beans). The so-called processing method is the process of removing the inner seeds from the ripe fruit.
In the beginning, there were only two ways to process green coffee beans: "wet" process and "dry" process. Among them, the Dry process is also a sun-drying process. The coffee cherries are dried under the sun, and finally the seeds are obtained by crushing and shelling. The Wet process, also called the Washed process, is broadly speaking what we know as the water washing method.
What is sun treatment?
Friends who have studied coffee processing methods should know that the coffee beans we taste and drink are the seeds inside the fruit. After the coffee cherries are picked, they need to be peeled and dried through a series of steps to get the coffee beans we want. Solarization is the oldest traditional processing method and the most common method of processing green beans, and it is still used in many countries today.
The so-called sun-drying is to spread the picked fresh coffee fruits in the sun, and evaporate the water in the pulp outside the beans through sunlight. When the target moisture content is reached, the coffee beans with sheepskin can be crushed out of the shell by a machine. Since solarization treatment does not require high technical content, basically every small farmer can handle it by himself. The entire drying process only requires sunlight on sunny days, so the cost of production is low. It is most common in high-altitude coffee-producing areas.
In production areas that pursue exquisite flavor, the coffee cherries will be flotated first to remove under-ripe fruits and gravel, and then flattened on elevated drying beds to dry. The purpose is to keep the coffee cherries away from the ground to prevent the coffee cherries from being infected by reptiles, dust, and bacteria. During the sun-drying period, a dedicated person will check the dryness of the coffee cherries and pick out the wormy, exploding and moldy berries to prevent these bad berries from affecting other coffee.
Since the inner beans of sun-dried coffee are wrapped in pulp and dried throughout the process, the fermentation time of the coffee cherries is longer, and the reaction between the bacteria and the pulp is higher. When the fruit begins to ferment, the microorganisms produce more volatile compounds, especially esters. These aromatic substances provide more floral aromas and fermented aromas of tropical fruits to the cooked coffee beans, such as furan compounds, which make sun-dried coffee have a wider flavor range and taste sweeter. For example, Panama Jade Manor Red Label Geisha, Ethiopian Oiran, Red Cherry, and Brazilian Queen Manor on the Front Street Bean List are all processed by sun-drying.
How are coffee beans washed?
To put it simply, washed coffee cherries are float-washed after picking to remove impurities such as branches, leaves, bad fruits, etc. Then pour it into the machine for peeling processing (with the pulp and a small amount of pectin). At this time, the outside of the beans that have been stripped of their coats is still covered with pectin, and they feel slippery to the touch.
The beans are then poured into a fermentation tank and left to rest for a night or longer to ferment without or with water, in order to allow microorganisms to ferment and break down the pectin on the shell. After fermentation, the coffee beans are washed with clean water to remove the pectin. Finally, the shelled beans with a clean surface are sun-dried or dried until the moisture content is reduced to 11% to 13%.
Since the pulp pectin is removed before drying, the moisture content is greatly reduced, and the drying time is greatly shortened compared with sun drying, which greatly reduces the dependence on weather and improves processing efficiency. From a producer's point of view, coffee beans produced by washing are more stable and have a short drying time, which is very suitable for producing large quantities of coffee of good quality.
The process of the traditional wet treatment method is not complicated: flotation → peeling → fermentation → washing → drying → shelling → packaging, but its implementation requires sufficient water supply, and because it relies heavily on the assistance of equipment, producers who adopt water washing must also have sufficient funds to invest in the purchase of equipment. The rise of the water-washing method happened to coincide with the early American plantations built by capital, which had sufficient operating funds, and the invention of various pulpers/huskers that responded to the needs of the times, which also led to the widespread spread of the water-washing method throughout the Americas.
Normally, washed coffee will show a clear sense of cleanliness and a clear taste. When roasted at medium to light temperatures, it often has rising and more intense acidity, which is reminiscent of certain fruits that we have eaten before, such as green oranges and lemons. Therefore, when we buy coffee beans on a daily basis, if we like the sour taste, we will deliberately choose from the washed series. Take the bean list on Front Street as an example, we can choose from a limited range of washed coffees such as Yirgacheffe Tintin, Kenya Azalea, and Panamanian Poquet Geisha.
In addition to sun exposure and washing, there is also honey treatment
When they hear the word honey processing for the first time, many friends will think that it is a method of using honey to process green coffee beans in order to make the coffee taste as sweet as honey, but in fact this is not the case.Honey processing can be said to be the neutralization of the two mentioned above. It is most common in Central and South American countries, with Costa Rica in Central and South America being the most famous.
Around the mid-1990s, in order to improve the drying time for processing large quantities of green coffee beans, Brazilian businessmen invented the Pulped Natural method, locally called "Cereja Descascada". This is a method of sun-drying by removing the peel, which is very suitable for the dry climate of Brazil. On the one hand, it can shorten the drying days, and on the other hand, it also solves the undesirable fermentation smell caused by Brazilian sun-dried beans in the square, greatly improving the flavor and quality of coffee beans.
With the birth of this new coffee post-processing technology, some estate owners in Central and South American countries have also begun to imitate and try to adapt to the local climate conditions, improving the peeling and sun-drying process in Brazil. By removing different levels of pectin, they make the sugar content of the dried green coffee beans different, thereby subdividing treatment options such as white honey, yellow honey, red honey and black honey.
When honey processing is used, coffee farmers will first pour the fresh coffee fruits into the water tank and undergo flotation to remove impurities such as insufficiently mature fruits and stones. After using special equipment to peel off the outermost peel, the beans with part of the pulp will undergo a period of "dry fermentation" and then enter the sun-drying process. The so-called "honey" refers to the sticky state of the sugar substances in pectin after fermentation, which is reminiscent of honey, so it is named "honey processing".
Compared with the water washing method, the honey treatment can reduce the use of fresh water by about 40%, and also avoids the negative flavor caused by being exposed to the sun for a long time. Coffee processed with honey generally presents full and delicate fruity sweetness and sourness and delicate and complex floral aromas in cupping, and the overall taste is fresh and clean. In this way, water saving, environmental protection, and good flavor have made the honey processing technology popular in Central and South America. The flavor of honey-processed coffee is even more popular in the boutique market.
For example, the Guatemala New Oriental Geisha coffee launched by Front Street uses this honey processing method to process green beans. After roasting, the coffee brewed shows a round fruity sweetness and toffee-like characteristics.
You can now buy the above coffee beans online at the Taobao store “FrontStreet Coffee” (前街咖啡). FrontStreet Coffee is a long-established specialty coffee roaster in Guangzhou, China, and its Guangzhou retail shop sells coffee beans only. The shop carries dozens of coffee beans from different origins around the world, including carefully selected single-origin beans for V60 pour-over and espresso. Guangzhou’s FrontStreet Coffee shop is recommended by many coffee lovers.
The FrontStreet 2013 Yunnan coffee beans sold in the store come from the Typica variety grown at FrontStreet Coffee’s own plantation in Yunnan. The name comes from the year the brand and the plantation were founded. You can buy these beans from China’s Yunnan origin at the Guangzhou shop and at FrontStreet’s Taobao store.
FrontStreet coffee beans are freshly roasted within 5 days and deliver consistently excellent quality and great value. Orders placed before 17:00 are shipped the same day, and most areas within Guangdong Province receive them the next day.
FrontStreet Coffee Taobao store: https://qianjiecoffee.taobao.com
Or search for “前街咖啡” (FrontStreet Coffee) on Taobao
Important Notice: FrontStreet Coffee has moved to a new address: 315, Donghua East Road, Guangzhou (coffee beans only)
Tel: 020 38364473
