How to turn coffee fruits into raw coffee beans? Does coffee raw bean fermentation belong to honey treatment?

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How to turn coffee fruits into raw coffee beans? Does coffee raw bean fermentation belong to honey treatment?

Most coffee producers in Taiwan are trapped in washing. On the one hand, they have misunderstandings, on the other hand, they have little knowledge of it, and on the other hand, they think they have amazing martial arts tips. As a result, the quality of coffee in Taiwan has been trapped in the pond for a long time and cannot be extricated. It is difficult for consumers to see what they really are. unfortunately!

Generally speaking, the reason for water-soaking fermentation is that the fermentation needs to be completed in water, and it is water that promotes the fermentation. This understanding may be partly correct, but it is not entirely correct. Due to the understanding of water-soaking fermentation, two methods of static water-soaking fermentation and live-water fermentation have been developed. I would like to express an idea here that there is nothing wrong with soaking in water and fermentation can be completed. However, no matter static water fermentation or live water fermentation, it is easy to produce pollution quality factors in the process. In other words, soaking in water fermentation is not easy to do.

At first, coffee fruits were harvested as long as they were laid in the sun until they were dried, which was the sun drying method. Very little water is used in the whole process. It is a way that can be operated by ordinary producers.

When the exocarp is peeled off, the producer is expected to shorten the drying time and reduce the mildew and other bad odors caused by damp rain in the sun process. But did not expect that the layer of colloid in the pericarp is more difficult to deal with. Therefore, I think of the method of removing gelatinous bodies with water, because gelatinous bodies are mainly composed of pectin and sugar and are easily dissolved in water. After removing the gelatin, the coffee beans are easy to dry and clean and easy to operate.

Therefore, in the early stage, it was thought that the purpose of fermentation was to remove colloid. After removing the colloid, the coffee beans are easy to dry and shorten the production time, resulting in a relatively large increase in production capacity. As a result, there are many super-large post-processing plants, which also turn post-processing into a kind of professional technology and equipment that producers can not touch. In order to increase production capacity and shorten the production process, a lot of degumming methods with biological or chemical additives are produced, combined with the application of drying machinery and equipment. The focus of this process is only on mass production of raw coffee beans. Most producers retreated to the role of coffee fruit supply and did not have the opportunity to participate in post-processing. Standard colonialist social patterns.

A large number of washed raw beans are produced, which relatively produces a large amount of waste water. The waste water discharged from coffee processing plants seriously pollutes streams in important coffee producing areas.

As the coffee consumer market is tired of the poor quality of mass production of washed beans, there is a growing demand for the improvement of coffee quality. Coffee quality improvement has become an important topic in various international discussions. in various resolutions, there are often plans to eliminate inferior varieties, upgrade high-quality coffee varieties, and improve coffee post-processing to improve coffee quality. With the introduction and completion of the concept of specialty coffee for selected coffee, more attention has been paid to the selection of coffee varieties, and various exquisite post-processing methods have gradually taken shape. Fermentation no longer focuses on removing colloid, but strengthening fermentation itself may increase the possibility of improving the quality of coffee. Emphasis is placed on finding the colloid inside the coffee fruit, which plays a role in affecting the quality of coffee. Therefore, the understanding of fermentation is no longer to remove the colloid, but what chemical changes have taken place in the whole fermentation process, which chemicals have been produced? And which chemicals are helpful to improve the quality of coffee? Which chemicals have a negative effect on the quality of coffee?

Based on the above intellectual understanding, there are relative expectations for the foreign experts invited to give lectures. In order to provide Taiwan coffee producers with an understanding of water washing, there was a workshop at the end of last year. Unfortunately, several attendees reflected that they only heard incomplete clips and thought that there would be dark steps in the training. Therefore, one of the purposes of this article is to supplement some information of the participants at that time, which can be used as a reference for making new beans this year.

The new concept of washing type mentioned earlier focuses on the importance of colloids in the quality of molded coffee. Therefore, the practice of removing colloids by water-soaking fermentation is no longer concerned about how long it takes to soak in water. Three washing styles are provided here for reference:

1. The first is the general washing type:

After harvest, the fruits with high quality and maturity are selected, peeled, fermented naturally for 12-24 hours, cleaned, soaked in water for 24 hours, washed and dried in the sun.

Note: the fermentation time at normal temperature is enough for one night, about 12-15 hours. It depends on the situation, it doesn't have to ferment to 24 hours.

two。 The second is the washing treatment of Rwandan coffee:

After harvest, the fruit with high quality and maturity is selected, peeled, fermented naturally for 12 hours, cleaned, fermented for 24 hours for the second time, cleaned, soaked in water for 20 hours, and dried.

3. The third is the so-called Kenyan style of washing:

After harvest, the fruit with high quality and maturity is selected, peeled, naturally fermented for 12 hours (to reach pH 4.5-4.8 whichever is whichever is), washed (80-90% colloid removed), naturally fermented for 24 hours, washed, soaked in water for 24 hours (water surface 5-7 cm), and dried.

Several points for attention in post-processing:

1. Pay attention to the maturity of the coffee fruit, use the sugar meter (diopter) to determine the refraction of the colloid as a reference, more than 18-20 indicates that the sugar content is sufficient, which is the best maturity fruit.

two。 Select the fruits after harvest, peel them and pick out the bad beans, and pick out the bad beans in the drying process.

3. The second and third methods both cut the fermentation into two times, and the first fermentation time is 12 hours. In terms of natural fermentation, it normally takes only 6-8 hours to have a good fermentation performance. After 3-4 times of full stirring fermentation, the coffee beans are fermented for 12 hours to achieve the overall full uniform fermentation effect. About 80-90% of the colloid can be removed by the first fermentation, and after cleaning, the second fermentation can be carried out to remove the remaining colloid. There is not much colloid in the second fermentation, such as the Rwandan style, although there is water-soaking fermentation, the chance of producing odor has been greatly reduced.

4. In the process of fermentation, pH meter was used to track the development of pH as a reference for the degree of fermentation. Generally, pH4.5-4.8is used for fermentation, and cleaning work is carried out immediately. However, pH4.5-4.8is only used as a reference for observing the degree of fermentation and may not be related to the best quality of coffee. Ask the post-processing operator to think about this meaning. The measured value of pH4.5-4.8indicates a critical point, which is greater than this critical point, which is the process of sprinkling semen fermentation; less than this critical point, it indicates that the acidity of the solution increases and has entered the process of extreme acetic acid fermentation. Please remember that fermentation refers to sprinkling fermentation (sugar decomposition) and lactic acid fermentation (lactose decomposition). Acetic acid fermentation should be avoided. These values are not only experience, but also have a theoretical basis, and are by no means nonsense.

5. Finally, soak the fermented and washed beans in water, the main purpose is to improve the quality of the coffee beans and make the raw coffee beans show a perfectly consistent blue-green hue. Early research papers mentioned that after washing coffee beans, if it is inconvenient to shop and dry in cloudy and rainy days, they can be soaked in clean water for one or two days and then sunny, which has little effect on the quality of raw beans. Here, this process becomes an important step in improving the color and stable quality of raw beans.

6. For a more accurate understanding of fermentation, please refer to several important principles such as sprinkling fermentation, acetic acid fermentation, and the generation of odor in the fermentation process.

7. In order to understand the difference of soaking coffee beans in different stages, coffee beans with colloid and those without colloid can be soaked in water for 12 hours, 24 hours and 36 hours, respectively. Compare the evolution differences between the two. After making this observation, it will add several times the power to the post-processing of your coffee.

8. Special warning: the time figure in the process is only a reference value, not an absolute value. The producer should find out the appropriate time value of his or her location and season.

Dry fermentation produces a soft and palatable aroma like ripe dried fruit and wine.

This is because the humidity in Yemen is drier than in Brazil.

However, the dry fermentation technology of Central American countries such as Panama is more advanced than that of Brazil.

The fermentation process strictly monitors the enzyme concentration, the content of coffee pulp and the temperature in the fermentation tank, etc.

Reduce the bad flavor that may be produced in the fermentation process.

Fully harvested coffee cherry fruit, remove the peel, pulp and pectin, take out the seeds, that is, coffee raw beans. The process of removing pulp and obtaining seeds is the so-called post-processing of coffee beans. The commonly heard treatment methods can be roughly divided into three types: sun exposure, water washing and honey treatment. The main difference between them lies in whether to retain the pulp / pectin and the fermentation management of coffee beans.

As mentioned above, the washing treatment is to peel and soak the coffee fruit after harvest, wash the mucous membrane after fermentation and dry it; honey treatment, the coffee is peeled without water and directly dried / dried; the sun treatment is obtained by drying the coffee fruit with belt meat.

The treatment method for the shaping of flavor lies in the management of fermented flavor. Whether coffee, tea or wine, the flavor of the drink is largely due to the aromatic substances produced by fermentation. The fermentation of coffee beans occurs between the harvest of coffee fruits and the complete drying of raw coffee beans.

Sun treatment, because the skin with fruit sun, retain the most sugar, take the longest time to dry, the highest degree of fermentation, fermentation flavor is also the most significant and strong.

Washing treatment, because at the beginning to remove the peel and pulp, leaving only the pectin attached to the coffee beans, soaked and fermented and then washed and dried, the fermentation flavor is relatively clean and fruity.

Honey treatment, peeling but retaining part of the pulp and intact pectin, drying directly without soaking, the degree of fermentation is between the sun and washing, and the flavor is also between the two, and then according to the different degree of fermentation, it is divided into white honey, yellow honey, red honey, black honey and so on.

Because the effect of fermentation is irreversible, once it goes too far, it can not come back. The control of fermentation degree greatly determines the quality of coffee bean flavor. Several key points of fermentation: sugar (fermentation raw material), water (fermentation condition), temperature (fermentation condition), oxygen (fermentation condition). Among them, water management / accurate drying is the key to the significant improvement of the quality of Taiwan coffee beans in recent years. In Taiwan's coffee producing areas, the sunshine conditions are not stable, and the changing range of drying time is too large, which will lead to instability of quality. Most of Taiwan's boutique coffee estates are equipped with dryers to control the fermentation schedule within a certain range through drying assistance, so as to ensure the complete drying and preservation of raw coffee beans.

In the past year or two, coffee farms in Taiwan have been exploring treatments such as "low temperature and low oxygen fermentation" and "anaerobic fermentation". The principle is that the effects of "aerobic fermentation" and "anaerobic fermentation" are different, and the flavor products produced by anaerobic fermentation are different. The fermentation flavor of anaerobic fermentation may have a slightly higher evaluation in terms of flavor evaluation, but the production process is still being tested, and it has been heard that it has achieved good results in the mid-altitude Nantou area.

Compared with the local soil and varieties, the fermentation flavor created by the treatment method is to a large extent artificially controllable, and the most direct presentation is the choice and preference of the coffee manor owner to the flavor. The flavor of post-processing can be said to be the most human flavor in the flavor of coffee and raw beans.