Why adjust the amount of powder when espresso is extracted?

When espresso is extracted, the amount of powder in the coffee means the thickness of pressed powder, while the thickness of pressed powder means the degree of uniform extraction of coffee, which also means the effect on the taste of espresso. Under high pressure, when hot water is used to extract espresso, the top of pressed powder will come into contact with hot water earlier than the bottom, and the flavor substances will be extracted faster.

When the hot water flows to the bottom of the powder bowl, not only the water temperature will decrease, but also the soluble substances in the water will be saturated, which will further reduce the extraction of coffee powder at the bottom of the powder bowl, resulting in insufficient or uneven extraction. In other words, the more powder, the thicker the pressed powder of coffee, the longer the path of water, which greatly increases the possibility of uneven extraction.

The thickness of pressed powder will determine whether the coffee will be underextracted or overextracted: if you are tasting espresso, when you taste the salty taste of the coffee, it means that the coffee may be underextracted, which can relatively increase the powder content of the coffee; if the coffee has obvious astringency and weak taste, there is the possibility of over-extraction, which can relatively reduce the powder content of the coffee.

When we extract coffee, the coffee will be from strong to light, this is because the amount of coffee ingredients in the coffee is slowly decreasing. The composition of coffee is different from what we think. It doesn't dissolve the same concentration from beginning to end, but it dissolves a lot at first and then becomes less.

Coffee liquid is a drink that dissolves the ingredients formed in the baking process into water. Therefore, depending on the concentration of coffee ingredients dissolved in water, the taste will also change. In the early stage, the concentration of the extract is high, the aroma and taste are strong, while the later extract is light. In the initial stage, about 20% of the extract has already dissolved about 80% of the coffee. In other words, the initial extract dissolves the most coffee ingredients, so it plays a role in determining the taste and aroma of coffee. In the later stage of the extract, the flavor will be released from the woody components in charge of the coffee bean structure, and more ingredients that determine the consistency and bitterness will be released.

By mixing the initial extract with water, you can get a lighter, softer, better-scented coffee, but the consistency and personality will be weakened. At this time, if an appropriate amount of coffee is added to the coffee extracted in the later period, the bitter taste will become slightly stronger, which can enhance the consistency under the condition of aroma and taste, and become a personalized coffee. The aroma and taste of the coffee extracted in the early and later stages are different. As long as you make good use of this point, you can skillfully adjust the taste according to your personality.