Why the flavor of sun coffee beans is more rich, and the washed coffee beans are cleaner?

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You may have heard a saying: the beans in the sun are rich in flavor, and the water is cleaner and sour. Is that really the case?

There are some clues to the flavor of coffee beans from the way they are handled.

Today, let's imagine the flavor of coffee from the process.

First of all, it is necessary to clarify a concept: treatment process = fermentation process.

The treatment of coffee beans is the process of picking coffee cherries from fruit trees and turning them into raw beans before baking. This process can also be regarded as the process of coffee bean fermentation. Just like wine is a wine that needs to be well brewed to produce excellent flavor, so the treatment is similar to raw beans. It is a combination of bacteria and coffee beans, which can lead to the hidden flavor of coffee beans.

So what kind of secret flavor will there be between tanning and washing?

To put it simply, the sun is used to dry the coffee cherries with pulp and peel, so it is called Nature in English, but this nature treatment seems easy but not simple, and he has made some efforts to improve.

The way to deal with the commercial sun is to spread a piece of plastic cloth on the ground and put the coffee beans directly on it for the sun; however, the problem will lie in the transfer of geothermal heat and the unstable heat convection of coffee cherries, if not stirred frequently, there may be problems of excessive heating or uneven fermentation. You can imagine that the beans laid on the top are very comfortable in the sun, and the beans stuffed at the bottom may smell funny.

In addition, there are many bad bacteria and pollution on the ground, which will also destroy the flavor of coffee beans. So there are a lot of traditional solarization. The flavor of the early good beans will not be treated by the sun, because people have a poor impression and the price is not high.

However, the tanning method has improved a lot in recent years. Most of the current sun treatment methods use African-style viaducts, which can effectively block moisture and soil on the ground and increase air convection. In the process of sun exposure, the temperature will also be strictly controlled to prevent the high temperature from causing excessive fermentation.

The whole process of sun treatment usually takes more than 20 days, allowing the bacteria and coffee cherry pulp to gradually ferment, so the flavor is relatively sweet, but also with rich tropical fruit flavor.

In the washing method, the harvested coffee cherries are peeled and pulped, and the remaining seeds and a layer of residual mucous membrane are thrown into the sink and fermented with water. The whole fermentation time is only about 24-30 hours.

The quality of the water washing method is obviously better than that of the sun exposure method. In the process of water washing, the defective beans floating on the water surface can be easily removed, and the flavor is not easy to appear because the fermentation time is short, and the beans are naked and washed in the sink, so the water washing method will show a clean and flawless taste.

In fact, the washing method can be subdivided into machine drying or sun drying, and unique washing methods will be developed in different regions, such as the Kenyan 72-hour washing method. Let's briefly introduce it first.

Kenyan washing method

Kenyan coffee is famous for its rich layers and clean taste. Its unique Kenyan-style water washing method goes through two water-washing and fermentation procedures, commonly known as "double fermentation". It is a rather complicated but delicate method of raw bean treatment. This treatment is more time-consuming and water-consuming than ordinary water washing, so Kenyan coffee is more expensive, but it is also an indispensable method to create a unique sour flavor and clean taste of Kenyan coffee.

First washing and fermentation

After the coffee cherry harvest, the beans will first be picked by the specific gravity of the water flow; the principle is that the coffee fruit itself is screened by the difference in density and quality; the coffee beans with high density (heavy weight) will sink into the water, while the coffee beans with low density will float. The coffee fruits with high mature quality have high density, so they are screened out for further treatment.

After the high-quality and ripe fruits are selected, the peel is removed, washed and soaked, and the pectin mucus attached to the outer layer of raw beans is fermented. Pectin has natural sugars and alcohols, which play an important role in the development of sweetness, acidity and overall flavor of coffee.

The fermentation time is as long as 24 hours. after fermentation, 80% of the pectin can be removed, leaving only the flavor in the coffee beans.

The second washing and fermentation

Then enter the second washing and fermentation process. After the coffee beans in the previous stage are cleaned, they are soaked in water for 12 hours and 24 hours. This process increases proteins and amino acids, and the acidity of coffee beans creates complex and delicate layers of taste.

Finally, remove all the remaining pectin and move the coffee beans to a high shelf for sun drying, depending on the weather, which usually takes about 5 to 10 days to complete.

But generally speaking, the beans washed with high quality and bright acidity, the flavor is also very clean, sometimes washing method can highlight the special flavor of coffee beans.

So do you get to the point of why the treatment affects the flavor of coffee beans?

The answer is: fermentation time and fermentation degree

Sun method, because beans and peel, pulp together with the sun, a higher degree of fermentation, but also for a long time, can usually develop more tropical fruit flavor.

The water washing method leaves only a thin layer of mucous membrane, and the overall treatment time is also relatively short. even the Kenyan 72-hour water washing method is much different from the sun drying method for a month, so you can imagine the beans washed in general. The flavor is cleaner.