What are the key elements of making good coffee? Introduction to the extraction principle of hand-made Coffee

Coffee extraction is a process of extracting substances from coffee powder by dissolving water through coffee powder, and it is also a scientific principle that can be tested. When the water comes into contact with the coffee powder, most of the water-soluble substances are taken out and fused with each other, and then the various coffee flavors, whether perfect or not, are extracted, and finally a cup of coffee is brewed. Coffee extraction is a complex chemical change, roasting state, bean powder blending, extraction powder quantity and water volume. Different parameters will change the aroma of coffee, but everything you want to brew a cup of coffee requires the fusion of powder and water, and the perfect coffee extraction helps to enhance the taste buds of drinkers. Therefore, the penetration of water through coffee powder has become a key action affecting coffee extraction.

Generally speaking, coffee extraction is the first to release the aroma and acidity of coffee, which is why as soon as the water passes through the coffee powder layer, the air is filled with coffee aroma, and the sweetness and bitterness will only be brought out in the middle and after. however, if excessive extraction (beyond the time after extraction), it will have too much bitterness and astringency, resulting in the final flavor of coffee is too thick and hollow, in addition Coffee particles are also more likely to be over-extracted if they are too fine (because coffee particles are quickly extracted, and if the water has not penetrated, they will become soaked) On the other hand, if the coffee particles are too thick, it is easy to underextract (because the water is already fully permeated when it is not in full contact with the water). Therefore, according to different brewing methods, match with the appropriate coffee powder thickness and various parameters. in order to interpret the coffee extraction perfectly.

Important parameters affecting Coffee extraction

Gold cup theory

According to the gold cup theory of the American Fine Coffee Association (SCA), the coffee concentration is between 1.15 and 1.45% and the extraction rate is between 18.22%, which is a necessary data condition for good coffee.

Coffee concentration

Less than 1.15%: too diluted and too light

More than 1.45%: too thick to drink and too strong to taste

Extraction rate

Less than 18%: too much acid, too much sharp discomfort

More than 22%: obvious bitterness, dry and negative taste

Following the above data, it can be found that the balance between coffee concentration and extracted substances is very important. If one side is too light, it will increase the proportion of the other, resulting in bad taste experience such as too sour or too bitter. Therefore, the gouache ratio has also become an important factor affecting the extraction.

About extraction

The longer the extraction time, the more suitable for coarse grinding of coffee particles; on the contrary, the shorter the extraction time, fine grinding will be selected. Only by accurately standardizing the extraction time can we show the unique flavor of coffee and make the final taste close to perfection.

Longer extraction time: suitable for rough grinding, taste refreshing, sour and sweet

Medium extraction time: suitable for medium grinding, taste balanced and sweet

Short extraction time: suitable for fine grinding, taste thick, pure and slightly bitter