Selection and purchase of raw coffee beans

Sellers of raw beans (usually coffee farmers or processing plants that deal with raw beans) must be responsible for the grading of coffee beans before they are sold to buyers (usually importers, brokers, or bean merchants). Once the classification is completed, the coffee beans of "Exceptional" and "Specialty" will still have some minor shortcomings that are not included in the classification, although these shortcomings are harmless. But it has a great impact on the performance potential of a coffee bean. You can tell from the appearance of raw beans how well a bean is handled. Although cup testing is the most accurate rule, looking at the appearance is usually a good way to judge.

The following are the points to pay attention to when observing the appearance of raw beans:

1. The size of raw beans should be very similar, 17hammer 18 mesh together, 15prime 16 mesh together, 13prime 14 mesh together, and so on. The appearance must be as consistent as possible, and the color should be similar. This project determines the color uniformity after baking and the difference in taste after baking. Beans with smaller grains and beans with larger particles are baked at the same time, resulting in an uneven baking degree, and therefore, the performance in the cup is uneven. The uneven color of raw beans is attributed to the problem of drying process, while the uneven appearance may be caused by the mixing of beans from different tree species.

two。 It must be determined that coffee farmers and processing plants are divided into batches according to the geographical growth areas and tree species of coffee trees. These batches must be harvested separately, processed separately, and tested in separate cups, before deciding whether to mix and store them in proportion.

3. Washed Arabica raw coffee beans must be uniform and glossy in appearance, and should not be uneven or dull in color. If this is the case, there must be something wrong with the drying process or the treatment process. If the color of raw beans is dull, the taste of drinking will also be dull.

4. First know the details of the drying process of raw beans, and if the estate puts a lot of effort into the drying process to ensure that the raw beans are properly dried, these efforts will be reflected in the cup. The use of improper balcony exposure or improper use of the dryer can usually be distinguished by the appearance: using the dryer to dry quickly will make the appearance of raw beans dull or brown; the appearance of raw beans has spots, it may be because the drying process is too fast, or the thickness on the balcony is too thin, or the speed of using the dryer is too slow. Some people suggest that the raw beans should be exposed on the balcony for a while to dry the skin, then transfer to the dryer, and then take out the balcony exposure for the final drying process, which they believe will help to uniform the color. In addition, some people bake the beans in the dryer every once in a while, and then put them back in the warehouse for storage, so that the moisture content of the beans will be more consistent, which is a very important step. Because the moisture content on the outside of the bean must be different from that on the inside. If you can, first ask the temperature used to dry beans, if more than 42 degrees Celsius, the cup may be more "baked", "dull".

5. No matter where you buy the beans, please ask about the "processing time". Make sure that the beans are sent to the processing plant as soon as they are harvested, otherwise you are likely to get a cup of overfermented coffee, because as soon as the beans are picked, they begin to ferment. Then ask them how to use the fermentation tank and why, and "whether to pick out the beans floating on the surface?" after the de-mucosal process, they "are separated into different sinks according to the hardness of the beans?" only manors that spend a lot of time and effort on quality improvement will understand the importance and necessity of these steps. If the mucosal removal process and washing treatment are carried out in the same tank at the same time, there will usually be some brown color on the surface of raw beans, and the same will happen on treated overripe beans.

6. Dried raw beans are usually covered with brown silver skins. In Brazil, this situation is called "Fox Bean" and is not included as a defect item. Novice bean pickers generally think that this is a defect, but if you rub the beans with a sieve a little bit, the silver skin will fall off, so this is not a flaw. Immature beans will also have silver skins adhering to the surface, but rubbing like the former cannot remove the silver skins. In the washed beans, "Fox Bean" shows a higher acidity, more fruity aroma, and sometimes more Rio flavor. The trend of the taste must be judged by drinking, not by visual observation.

7. "is there a pink silver skin covered in the cracks or on the surface of the beans?" in some areas, this phenomenon is considered a great defect, but most people will ignore this defect, for the simple reason that this item is not listed as the defective bean standard in the coffee bean grading system, so this kind of coffee beans may be classified as "Specialty" and go into the hands of buyers. Beans in this kind of situation are best tested separately from other beans to find out whether the degree of defect is serious.

8. "is it white or dark around the raw beans?" the reason is that the drying time is not enough, or the storage environment is too wet, the performance in the cup is empty, very boring taste. Whitening around beans can also occur in beans where the drying process is uneven, meaning that one side of the same bean is dried and the other side may be fine. The whitening of beans is caused by oxidation, contact with the ground, or contaminated by sewage.

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

10. How does it feel to grab a handful of raw beans? If they feel brittle, like glass, they may be too dry or too hot to dry. If you feel too soft and may not dry enough, you must return the beans immediately, because the raw beans under this moisture content are very easy to mildew.