Coffee Xiaobai classroom, coffee raw bean treatment, grading of honey treatment

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Coffee has become the darling of the beverage industry because of its strong flavor, round taste and mellow taste. People's busy work is inseparable from the refreshing effect of coffee, and people's leisurely life is inseparable from the pleasant embellishment of coffee. The love of coffee drives people to study coffee constantly. In order to show the flavor of coffee more incisively and vividly, more and more kinds of coffee are produced after "processing", such as Kopi Luwak, bird shit coffee and shit-like coffee and so on.

These expensive coffees are loved by coffee lovers all over the world because of their unique taste. When it comes to these expensive coffee, we have to mention its production process. According to Fulaigao coffee experts, the treatment of these precious coffee is different from that of other coffee. It uses "honey treatment".

Honey treatment is a kind of treatment between sun treatment and water washing. It keeps the coffee clean after washing, and although the brightness of the coffee decreases, it increases the sweetness and caramel taste. According to the different degree of honey treatment, honey-treated coffee can be divided into yellow honey treatment, red honey treatment and black honey treatment.

The appearance of honey-treated beans has an obvious sticky layer, but the honey treatment method is very dependent on the local climate, the weather must be dry and adequate sunshine, otherwise it is not suitable for honey treatment.

I. Anatomy of coffee fruit

The coffee fruit is divided into five layers.

These five layers are:

1. Skin/Pulp: the outermost layer of coffee beans is covered with berry-like skin and pulp. In addition to the natural sun method, coffee beans treated by other methods must remove the skin and flesh within a few hours after picking. Similar to the cherries we often eat, the difference is that when we eat cherries, we mainly eat the pulp and peel of berries. For coffee, peel and pulp are important by-products. In some places, people use the peel and pulp of coffee to make tea. People in the industry used to call the peel and pulp of coffee "Pulp". The machine used to remove the pulp is called the "desizing machine".

two。 Mucous membrane (Mucilage): under the skin and pulp, a thick layer of mucus tightly wraps the coffee beans. Because this mucous membrane is extremely sticky and high in sugar, it is used to call it "Honey". Not only coffee, but also many fruits have a layer of mucus inside.

3. Parchment (Parchment): inside the mucous membrane, a thin film of cellulose surrounds the coffee beans. After drying, the film looks like parchment, hence the name.

4. Silver Skin/Chaff: there is a thinner film inside the parchment that wraps the coffee beans. Because the color is glossy and silvery, people used to call it "silver skin". This layer of silver will fall off during baking. Usually when you grind the coffee, you find some silver crumbs in the coffee powder. These crumbs are the silver skins that fail to peel off the coffee beans during baking.

5. Coffee beans: each fruit contains 2 coffee beans (except for a single pod bean Peaberry. The fruit of this kind of coffee contains only one coffee bean. Normally, 5% of each batch of coffee beans is a single pod. Coffee beans can be roasted after drying and processing.

Second, three major treatment methods of raw coffee beans.

We know that the treatment of raw coffee beans can be roughly divided into three types. The distinction between each method is based on the fact that several layers of matter are removed from the fruit before the coffee is dried.

1. Natural sun treatment: retain all substances

two。 Honey treatment: remove the peel and pulp and retain some or all of the mucous membrane (honey)

3. Washing method: the peel, pulp and mucous membrane are removed by washing and fermentation. This method is also known as the complete washing method (Fully Washed). Washing is the most common way to treat Arabica coffee beans in most coffee-producing countries in the world. Some areas also use advanced high-pressure washing machines to clean the peel, pulp and mucous membrane of coffee beans, so fermentation is no longer needed. This method of using a high-pressure washing machine to treat coffee beans is called "natural washing (Pulped Natural)".

From the point of view of the removal of substances and water consumption during coffee treatment, honey treatment is between the sun treatment method and the water washing method.

Third, analyze each method of raw bean treatment:

1. Natural solarization (Natural/Dried-in-the-Fruit):

The process of this method is the simplest. The fruit begins the process of sun drying without treatment after picking. This is the oldest method of treatment in existence. This method is still used in places such as Ethiopia and Brazil. Natural solarization is most common in areas where water resources are scarce. The drying process usually lasts about 4 weeks. The method of handling must be very strict to ensure that the coffee does not lose any flavor. The natural sun method requires the local climate to be extremely dry. In some areas, people use dryers to assist in the drying process of coffee fruit (the hot air of the dryer can speed up the drying process and help people control the degree of drying).

Natural sunlight can retain the fruity aroma of coffee fruit. When you taste this kind of coffee, you will find that the coffee has a fruity aroma and a brighter taste. After drying, people will use special machines to remove the shell of the surface layer. This process is called drying and shelling (Dry Milling).

two。 Washing method (Washed)

In the process of washing, the peel and pulp of the fruit are treated with a special desizing machine and the coffee beans are peeled off. The coffee beans then enter the fermentation tank for fermentation treatment so that the mucous membrane is no longer sticky. The sugars in the mucous membrane are decomposed during fermentation. Depending on the fermentation method, the fermentation time is usually 12 hours to 6 days (some growers use the watering system to ferment coffee beans. This method is called the Kenyan washing method (Kenyan method) and usually lasts for several days). It is extremely important to decide when to stop fermentation. Once the coffee is overfermented, the taste of the coffee will become too sour. Once the sticky material in the mucous membrane is decomposed, it will be washed down with a lot of water. (the waste water from the raw bean treatment process is considered to be the source of pollution in the coffee industry. Today, advanced technologies are being developed in many areas to recycle and filter the waste water produced by this process. Water shampoo was born in the 19th century, also known as "wet processing".

A tightly controlled fermentation process increases the acidity of the coffee and is reflected in the final taste of the coffee. But as long as the coffee is washed immediately after the fermentation process, the taste of the coffee can be improved and has a bright sour taste.

3. Natural washing (Pulped Natural)

This method is extremely common in Brazil. The natural washing method is very similar to the water washing method, except that the natural washing method uses a high-pressure washing machine to remove the mucous membrane of the coffee surface, thus skipping the fermentation process. Several raw coffee processing companies in Brazil and Colombia have patented this method and have become local natural water system processing monopolies. The amount of water used in this method is much lower than that of washing hair, so some people are used to calling it "semi-drying (Semi-Dry)". Because there is no fermentation, coffee beans do not exist (or only have a very low risk of fermentation), and the overall quality of coffee is more constant. Unfortunately, the taste of coffee tends to be flat because it is not fermented. As a result, growers will not use natural washing for ultra-high quality coffee beans. Most raw bean purchasing companies also rarely buy coffee processed by natural washing.

4. Honey treatment method

Today, honey treatment is used in almost all the producing areas of Costa Rica. This method is also widely spread throughout Central America. Because the surface mucosa of coffee beans is extremely slippery and the sugar content is extremely high, it is often called "honey". In the process of honey treatment, coffee will leave some or all of the "honey" when it is dried. After the coffee fruit is picked, graded and peeled, it is placed on a drying bed to dry.

Because the drying time of the mucous membrane is very short, coffee beans hardly ferment during the drying process. The acidity of coffee beans processed by this method is slightly higher than that of natural washing, but much lower than that of natural washing and natural sun processing.

IV. Color grading of honey treatment

Today, some Costa Rican growers grade honey-treated coffee beans according to the color of the coffee. There are three levels: yellow, red and black. The change in color results from the length of light during the drying process of coffee.

The light time of raw coffee beans treated with yellow honey was the longest. Longer light means higher heat, so the coffee can be dried within a week. In general, the drying time of coffee depends on the local climate, temperature and humidity. The drying time of raw coffee beans treated with red honey is 2-3 weeks, usually due to weather or placed in a dark place. If the weather is clear, the grower should block part of the sun to reduce the sunshine time. The coffee beans treated with black honey were left in the dark for the longest time and the shorter the light time. The drying time of this coffee is at least 2 weeks. The black honey treatment of raw coffee beans is the most complex and the labor cost is the highest, so the price is the most expensive.