Selection and purchase of raw coffee beans (industry)

How to buy raw beans? What kind of green beans are good green beans?

Green bean sellers (generally refers to coffee farmers, or centralized processing plant) must be responsible for the classification of coffee beans before selling to buyers (generally refers to importers, brokers, or bean dealers). Once the classification is completed, the coffee beans of the two grades of "Exceptional" and "Specialty" will still have some minor defects that are not included in the classification. Although these defects are harmless, they have a great impact on the performance potential of a coffee bean. You can tell how well a bean has been treated by the appearance of the raw bean. Although cupping is the most accurate rule, appearance is usually a good way to tell.

Here are some things to note when observing the appearance of raw beans:

1. Green beans should be very similar in size, 17/18 together, 15/16 together, 13/14 together, and so on. The appearance must be as consistent as possible, and the color should be close. This item determines the uniformity of color after baking and the difference in taste after baking. Roasting smaller beans at the same time as larger beans results in uneven roasting, and therefore uneven taste in the cup. The uneven color of green beans is attributed to the drying process, while the uneven appearance may be caused by the mixing of beans from different tree species.

2. It must be established that coffee farmers and processors divide batches according to the geographical growth area and species of coffee trees. These batches must be harvested separately, processed separately, and tested separately before deciding whether to mix and store them in proportion.

3. The washed Arabica green coffee beans must be uniform in color and shiny in appearance. There should be no uneven color or dull color. If there is such a situation, it must be a problem with the drying process or the processing process. If the color of raw beans is dull, the taste of drinking will also be dull.

4. Learn the details of the green bean drying process in advance. If the farm puts a lot of effort into the drying process to ensure that the green beans are properly dried, these efforts will be reflected in the performance of the cup. Improper use of balcony exposure or improper use of the dryer, usually can be distinguished by appearance: rapid drying using the dryer, will make the appearance of raw beans dull color, or look brown; the appearance of raw beans has spots, it may be because the drying process is too fast, or the thickness of the balcony is too thin, or the use of the dryer speed is too slow. Some people suggest drying the green beans in the sun for a while on the balcony, then transferring them to the dryer, and finally taking them out for the final drying process. They believe this practice helps to even out the color. Some people put the shelled beans in the dryer at regular intervals and then put them back into the warehouse for storage. This way, the moisture content of the beans will be more consistent. This step is very important because the moisture content of the outside beans must be different from that of the inside. If you can, first ask the temperature used to dry the beans, if it exceeds 42 degrees Celsius, it may be more "baked taste" and "dull" in the cup.

5. Regardless of where you buy beans, ask questions about "processing time." Make sure the beans are sent to the processing plant as soon as they are harvested, otherwise you are likely to get a cup of coffee that is too fermented because the beans begin to ferment as soon as they are harvested. Ask them how they use the fermentation tank and why, and "Do you remove the beans floating on the water?" After the de-mucilage process, they asked,"Do they separate the beans into separate tanks according to their hardness?" Only those estates that spend a lot of time and effort on quality improvement understand the importance and necessity of these steps. If the de-mucilage process is carried out in a water tank simultaneously with the washing process, it is usual for the green beans to have some brown color attached to the surface, and the same situation will occur on the treated over-ripe beans.

6. In Brazil, this condition is known as "Fox Bean," and is not included in the defect project, the general novice bean picker will think this is a defect, but if you rub these beans with a sieve, the silver skin will fall off, so this is not a defect; not fully ripe beans will also have silver skin attached to the surface, but like the former rubbing, can not remove the silver skin. In the washed beans,"Fox Bean" presents a picture with higher acidity, richer fruit, and sometimes more Rio flavor. As for the direction of taste, it must be judged by drinking, not by visual observation.

7. "Are the beans covered with pink silver in the cracks or on the surface?" In some areas, this phenomenon is regarded as a great defect, but most people ignore this defect, the reason is simple, because in the coffee bean classification system does not list this item as a defective bean standard, so this kind of coffee beans may be classified as "Specialty" grade, into the hands of buyers. Beans with this condition are best tested separately from other beans to see if the defect is severe.

8. "Are the green beans white or dark?" The reason is that the drying time is insufficient, or the storage environment is too humid, and the performance in the cup is empty and boring. Whitening around the beans can also occur in beans that have been unevenly dried, meaning that one side of the same bean is drier and the other side may be fine. Whitening of beans can be caused by oxidation, contact with the ground, or contamination by sewage.

9. Smell the green beans. Excessive fermentation or soot contamination can be detected at this time, and these flavors may become imperceptible after baking.

10. Grab a handful of raw beans, how does it feel? If they are brittle to the touch, like glass, they may be overdried or overdried. If it feels too soft to the touch, it may not be dried enough, and such beans must be returned immediately, because raw beans at this moisture content are extremely moldy.