What are the advantages and disadvantages of washing and tanning? What's the difference between them?

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What are the advantages and disadvantages of washing and tanning? What's the difference between them?

The influence of coffee flavor, in addition to varieties, producing areas, planting methods, there is also an important process-coffee raw bean treatment. Different treatments will lead to different flavors of coffee beans. Generally speaking, it is common to hear that raw beans are treated by "sun exposure" and "washing". What is the difference between these two methods?. Let's have a look today.

The secret of the construction of coffee beans

Before we understand the method of raw bean treatment, we must first understand the structure of coffee fruit! The coffee fruit appears green at first, and then gradually ripens to red, yellow or orange according to the variety. Because the appearance is similar to the shape of a cherry, it is also known as "coffee cherry".

Coffee beans-washed and insolated

Generally speaking, the roasted coffee beans on the market are actually the seeds inside the coffee fruit. usually there are two seeds (sometimes only one) in each coffee fruit. the outer-to-inner structure is exocarp, pulp, pectin layer, endocarp (seed shell), silver skin, seed, and the processing method of sun or water washing is to remove these external structures. To get the internal coffee seeds (coffee beans).

Coffee beans-washed and insolated

Solarization method

Sun drying is the oldest and most primitive treatment of coffee beans. compared with the water washing method, this dried coffee is also called "natural coffee" or "sun-dried coffee." the harvested coffee fruits are directly exposed to the sun for about two to four weeks. This method is generally used in countries with a clear dry and wet climate.

"Solar method-treatment process"

Coffee beans-washed and insolated

1. Harvest ripe coffee fruit

two。 Preliminary selection of impurities and inferior beans

3. Select floating beans: pour the coffee fruit into the sink, the ripe and full fruit will sink to the bottom of the sink, and the immature or incomplete fruit will surface.

4. Sun drying

Coffee beans-washed and insolated

Take out the ripe coffee fruit that sank at the bottom of the sink and spread it in the sun-drying field to reduce the moisture from 70% to about 10-12%. Turn the fruit several times a day to dry evenly, and cover it at night to avoid moisture.

5. Remove the shell: after about two to four weeks of exposure, the outer layer of the coffee seed has become dry and hard, and then use a sheller to remove the shell.

6. Packaging and transportation

After shelling, the coffee beans will be packed in a bag, which is also what we generally call raw beans. Finally, after different roasting processes and brewing changes, it can show the taste changes of millions of kinds of coffee.

"Solar method-advantages and disadvantages"

Advantages: the treatment process is very simple, does not need to invest too many tools and equipment, and except for the steps of removing floating beans, it does not need to use water, the cost is low, and it is widely used in areas where water resources are not abundant and less affluent.

Disadvantages:

1. Enough space is needed for exposure, and because coffee beans have to be placed outdoors, fallen leaves, insects and other impurities are often mixed in.

two。 The intensity of sunlight varies every day, so it is difficult to control the dryness of coffee beans.

3. It takes more manpower to turn regularly in order to ensure that mildew and decay will not occur.

Coffee beans-washed and insolated

At present, there is an improved design of "African viaduct". The weaving net with tripod can avoid moisture and soil impurities on the ground, and the air convection makes the curry fruit more ventilated and dry evenly.

Washing method

The technology of washing was invented by the Dutch in the 18th century. Because of the frequent rain and high humidity in some countries, it is impossible to implement the sun method at all, so although the process is relatively tedious, it is the most widely used treatment method at present. The biggest difference from the sun method is the use of fermentation to remove the pectin layer.

"washing process-treatment process"

Coffee beans-washed and insolated

The first three steps are the same as the sun treatment (1. Harvest ripe coffee fruit 2. Preliminary removal of impurities and inferior beans 3. Screen floating beans)

4. Remove the peel and pulp: the selected good coffee fruit is put into the pulp sieving machine to remove the exocarp and pulp and leave seeds (coffee beans).

5. Pectin removal by fermentation: put the coffee seeds with a layer of mucous membrane (pectin) in the fermentation tank and use biological treatment to dissolve the pectin by fermentation bacteria.

6. Washing to remove impurities: since the fermentation bacteria will remain on the coffee beans, the beans need to be sent to the washing pool for a second screening (defective beans will float on the surface). This step will consume a lot of clean water in order to clean it up.

7. Coffee bean drying: coffee fruit is usually dried by machine (or sun drying) so that the moisture content is reduced to 1014%.

8. Remove endocarp and silver skin: finally, use a sheller to remove the remaining endocarp and silver skin, that is, complete the processing, you can carry out the packaging and transportation of raw beans!

"washing method-advantages and disadvantages"

Advantages: coffee beans have fewer impurities and more complete appearance, and because the pulp in the coffee fruit has been removed from the very beginning, there is no need to worry about mildew, and the overall quality is more stable.

Disadvantages: the process of washing is complex and tedious, and requires a lot of water, so the cost is relatively higher than the sun method, and it is less used in areas where water resources are scarce.

Is it better to make coffee beans in the sun or in water?

Sun beans have a sweet and sour taste of tropical fruits, leaving coffee beans naturally mellow, rich in flavor, and sometimes with a hint of wine! On the other hand, because the fermentation process of washed beans is better controlled, the flavor of washed beans is not as sour and bright as sun beans.

The flavor of coffee beans as mentioned earlier, in addition to coffee raw bean treatment, coffee bean varieties, origin, roasting, brewing, preservation, and so on, there are many factors.