Kopi Luwak | Civet Cat Digestive Fermentation Principle? Sidamo Guji Premium Natural Fermentation Processing Method?

Civet Coffee | Fermentation Principles in the Civet Cat's Body? Sidamo Ardi Natural Process Fermentation?

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Natural Process: Creating Intense Wine Aromas

The natural process is the most primitive, simple, and time-honored coffee processing method. According to relevant literature, as early as over 1000 years ago in the 11th century, Arabs began using the natural process to handle coffee fruits.

Processing Steps:

First, coffee beans are poured into large water tanks, where underdeveloped inferior beans float on the surface. The mature, full fruits that sink to the bottom are scooped up, spread evenly for sun exposure, frequently turned, and defects are sorted out.

When the moisture content inside the coffee beans drops to 10%-14%, a hulling machine can be used to remove the skin and pulp, completing the entire natural process.

Disadvantages:

The natural process is completely dependent on weather, making it difficult to control the dryness of coffee fruits. If the drying area is not clean, impurities can easily mix in. During the natural drying process, the pulp of coffee fruits is not removed, so mold and rot often occur. Therefore, in many people's view, naturally processed coffee beans have poor quality controllability and won't achieve high grades.

Advantages:

Except for the first step of filtering out inferior beans with water, the natural process doesn't require any water in other steps and can be reused repeatedly. In regions with limited water resources, this method is simply excellent. Additionally, because natural beans have irreplaceable special flavors, some excellent estates have begun to seriously treat natural beans, such as placing them on racks to prevent contamination and careful selection, allowing us to see many high-quality natural coffee beans today.

Flavor:

Although natural beans have uneven appearance and significant color differences, because coffee beans mature naturally inside the fruit without interference from the external environment, naturally processed coffee beans have more intense flavors, with wine-like fermentation notes and sweetness.

Washed Process: Creating Clean Acidity

Due to the disadvantages of the natural process, in the mid-18th century, the Dutch invented the washed process, which gained widespread popularity. The biggest difference from the natural process is that it uses fermentation to remove the outer skin.

Processing Steps:

Like the first step of the natural process, inferior beans are removed first, then a pulping machine is used to remove the skin and pulp of coffee fruits, which are thrown into water tanks for 16-36 hours of fermentation. Fermentation bacteria dissolve the mucilage.

To remove residual fermentation bacteria and impurities, the coffee beans are cleaned again, then machines are used to dry the coffee fruits until moisture content drops to 10%-14%. Finally, a hulling machine is used to remove the silver skin wrapping the coffee beans to complete the process.

Disadvantages:

As the name implies, the washed process mostly requires water, and in some countries lacking water resources, this processing method cannot be widely adopted. The washed process is also relatively cumbersome and much more expensive than the natural process.

Advantages:

It undergoes multiple layers of screening and cleaning, resulting in cleaner and more uniform appearance and taste. Also, because the pulp is removed at the beginning, there's no need to worry about mold issues like in the natural process.

Flavor:

Washed beans typically have bright, clean acidity because acidic substances are developed during fermentation in the fermentation tanks.

Semi-Washed Process: Removing Both Skin and Mucilage

Because the washed process requires too much water, the semi-washed process emerged. It's a hybrid of the natural and washed processes, representing a compromise between the two.

Processing Steps:

First, like the two processing methods mentioned above, inferior beans are removed. Then coffee fruits are poured into a pulping machine to remove the skin and pulp.

To reduce water consumption, the semi-washed process uses a demucilager to remove mucilage, finally drying the coffee fruits with machines or sun-drying them outdoors.

When the moisture content of coffee fruits drops to 10%-14%, a hulling machine is used to remove the silver skin sticking to the coffee beans, completing the process!

Disadvantages:

Although it's a hybrid of washed and natural processes, its procedure is as cumbersome as the washed process.

Advantages:

It has the cleanliness of the washed process without requiring large amounts of water.

Flavor:

The semi-washed process has the fewest variables affecting quality. The coffee acidity is slightly lower than washed beans but higher than natural beans; sweetness is lower than honey-processed beans but cleanliness is better than honey processing, with flavor between honey and washed processes.

Honey Process: Extracting Sugar from Mucilage

The honey process (called "Miel Process" in Spanish) is also known as the semi-natural process. It's the most trendy and distinctive processing method in recent years. Its main difference from the natural process lies in whether pulp removal occurs before or after sun-drying.

Processing Steps:

Similarly, the first step is still removing inferior beans, then using a pulping machine to remove skin and pulp, followed by sun-drying to reduce the moisture content of coffee fruits to 10%-14%. Finally, a hulling machine is used to remove the silver skin sticking to the coffee beans to complete the process.

Disadvantages:

Among the mainstream coffee bean processing methods, it's considered the most complex and demanding.

Advantages:

It's an improved version of the natural process, effectively solving the mold problem in coffee beans while reducing water costs.

Flavor:

Because it's sun-dried with mucilage, the sugar in the mucilage enters the beans during the drying process, resulting in balanced sweet and sour flavors with rich body. In recent years, many competition award-winning beans come from honey processing, with Costa Rica's honey processing being particularly famous.

Fermentation Process (Civet Cat Internal Fermentation)

Animal Internal Fermentation: Creating Gentle, Mellow Aromas

Regarding animal internal fermentation, the author personally finds it extremely cruel, with the most typical example being civet cat coffee (kopi luwak).

Principles:

It uses lactic acid bacteria and digestive fluids from the animal's digestive tract to remove pulp and mucilage attached to the bean surface. The beans are excreted with feces, and after cleaning, they become precious internal fermentation beans. Besides civet cats, animal internal fermentation beans include guans, monkeys, and elephants, but the latter few haven't formed large-scale operations, with only civet cats standing out.

Initially, this was because civet cats come out at night, relying on vision and smell to specifically pick the reddest coffee fruits, showing no interest in half-ripe green fruits, so the excreted beans are all perfectly ripe specialty beans. After these fecal beans are cleaned and roasted, all bacteria are killed. Their greatest characteristic is gentle flavor with enhanced mouthfeel, while the fundamental flavor depends on the coffee varieties eaten by the civet cats.

In New York, a pound of civet cat coffee costs five hundred dollars, while in Hong Kong, a cup of civet cat coffee costs fifty dollars. Later, people discovered this business opportunity and began large-scale civet cat farming, constantly feeding them coffee beans to produce more kopi luwak for profit.

In reality, different production regions will "adapt to local conditions," adopting the most suitable fruit processing methods. When a coffee bean reaches your cup, coffee farmers must consider not only costs but also what processing method is most suitable for that coffee fruit to make its flavor more prominent and delicious.

FrontStreet Coffee Recommended Brewing [V60 Pour-Over]:

Dripper: Hario V60

Water Temperature: 88°C

Grind Size: Fuji Royal grind level 4

Brewing Method: Water-to-coffee ratio 1:15, 15g coffee grounds. First pour 25g of water for 25s bloom. Second pour to 120g then stop pouring. Wait until the water level in the coffee bed drops to half before continuing to pour. Slowly pour until reaching 225g total water. Extraction time around 2:00.

Analysis: Using three-stage brewing to clearly distinguish the front, middle, and back-end flavors of the coffee. Because V60 has many ribs and faster drainage, stopping pouring can extend extraction time, better extracting the nutty and chocolate flavors from the back-end.

Important Notice :

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Tel:020 38364473