How to check whether a cup of espresso is standard

For professional baristas, please follow the coffee workshop (Wechat official account cafe_style)

Standards for espresso:

In the process of extraction, if it is found that the state of the coffee liquid will soon become unstable, a large jump, and the color will soon become very light, at this time, we can judge: there is a problem inside the pressed powder (cracks appear) or the uneven pressing of the coffee powder makes the less part of the coffee powder overextracted (and this is probably due to the uneven distribution of the powder) or the uneven distribution of the powder. So that the edge is not covered with coffee powder, causing the water to flow directly through there.

Observe pressed powder, after excluding factors such as pressed powder perforation, if the extraction time becomes longer, it may be over-extracted on the surface, but not enough on the inside, showing acidity, because it is not sweet enough, and then it is bitter and astringent, then the powder may be too fine, and you can thicken it a little bit at this time. But if the flow rate of coffee becomes faster, the current is thick, the extraction is light, the color is white, and the flavor is sharp and sour, it may be a little thicker, and it can be adjusted slightly at this time.