Why does the drip filter coffee machine need coffee to be ground thicker?

Why does the drip filter coffee machine need coffee to be ground thicker?

After grinding, the cell wall of coffee beans will completely disintegrate, which means that the area of contact with air will increase a lot, all lines of defense to protect freshness will be completely removed, and the rate of oxidation and deterioration will become faster, which will make the coffee lose its flavor within 30 seconds to 2 minutes. Therefore, the author strongly suggests: do not buy coffee powder, it is best to buy coffee beans, and grind them before drinking, and brew them as soon as possible.

Incidentally, the Turkish copper pot, shaped like a spoon with a long handle, is filled with coffee powder, water and sugar and boiled over the fire. This method of extracting coffee, known as "boiling", uses a deeply roasted, finely powdered coffee powder. Why use deep-baked coffee powder? The astringent taste of light-roasted and moderately roasted coffee powder will be enhanced after being boiled at high temperature, while using deep-baked coffee, even if extracted at high temperature, the coffee is completely bitter.

The above problem is also a matter of degree. If the grinding is too rough, the hot water will easily pass through the filter paper, and the delicious ingredients of coffee can not be fully extracted. In this way, the coffee from the coffee pot becomes a light, thin liquid.

Each coffee utensil has its own suitable degree of grinding, so we don't use whatever degree of grinding we want. As mentioned above, the coffee powder is too coarse or too fine to make coffee, that is to say, the most suitable grinding degree is medium to medium roughness.

According to the size of coffee powder after grinding, coffee bean grinding can be divided into three types: rough grinding, medium grinding and fine grinding. When grinding beans, the size of the powder depends on the way it is cooked. Grinding coffee powder with the right thickness is very important for making a good cup of coffee, because the extraction of water-soluble substances in coffee powder has its ideal time, if the powder is very fine and cooked for a long time, resulting in excessive extraction, the coffee may be very bitter and lose its aroma. On the other hand, if the powder is coarse and cooked too fast, resulting in insufficient extraction, the coffee will be tasteless because it is too late to dissolve the water-soluble substance in the powder. Generally speaking, the shorter the cooking time, the finer the ground powder; the longer the cooking time, the thicker the ground powder. In terms of actual cooking, the ESPRESSO machine takes a very short time to make coffee, so the coffee powder is the finest, and the coffee powder is as fine as flour; it takes more than a minute to cook coffee in the "plug air" way, and the coffee powder is ground in medium thickness; American filter coffee takes a long time to make, so the coffee powder is ground the thickest, one by one like grams on a shell beach.