The relationship between Coffee Grinding and Coffee extraction the main points of hand Coffee

Grinding is the process of grinding coffee beans into fine particles. Its primary aim is to increase the contact area between coffee and water, thus making extraction easier. Today, Chongqing Brista professional coffee training teacher came to analyze with friends the influence of coffee powder grinding on coffee making.

Grinding degree and contact time

The coffee powder with finer grinding degree has a larger contact area with water, and the extraction rate of coffee is faster. Therefore, in order to achieve a fixed total amount of extraction, the contact time between finely ground coffee powder and water is much less than that of rough ground coffee powder.

Distribution of particle size

Due to the different sizes of the coffee beans and the uneven grinding strength, the size of each coffee particle is different. In general, the sizes of most coffee particles are concentrated in the range of "grinding parameters" set in advance. In addition, the coffee powder with a small number of large particles in coffee is called "large particles"; the coffee powder with very small remaining quantities and very fine particles is called "very fine particles".

The smaller the distribution range of particle size, the more uniform the extraction of coffee. If the distribution range of particle size is too large, that is, there are a large number of coffee powder with too large particles and too small particles, the final coffee will have the negative taste of a lot of over-extraction and insufficient extraction.

The distribution range of coffee particle size will be reduced only when the bean grinder needs to meet the following requirements:

1. Sharpening the knife / grinding the gear is sharp enough

two。 The space in the grinding chamber is large enough.

3. Very little heat is produced in grinding.

4. Multi-step comprehensive consideration (for example, a hand bean grinder with two or three pairs of grinding gears)