What is the pre-soaking time of espresso machine

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After five minutes of talking to the barista, you will begin to hear all kinds of terms and techniques. It's like listening to a new language and learning a new technology.

If you focus on espresso, you will learn that one word is "pre-soaking", which refers to the process of moistening the pressed powder with a small amount of water before fully applying the extraction pressure required by the pressed powder.

The aim is to ensure that water permeates the pressed powder evenly so that the powder beds have the same amount of water flowing at the beginning of the extraction. After many tests, it is found that "pre-immersion" can effectively reduce the generation of channels and avoid the possibility of over-extraction and under-extraction at the same time.

However, as to whether pre-soaking has a substantial effect on the taste of coffee, we have also done comparative experiments with coffee that has not been pre-soaked. After tasting numerous cups of concentrated coffee, we have come to the conclusion that:

5s pre-soaking: bright acidity and smoother taste, taste and flavor have better structure and layering

10s pre-soaking: bright acidity and mellow Body, with insipid flavor and shorter aftertaste

15s pre-soaking: slightly sour, more round Body with increased sweetness and flavor complexity

30s pre-soaking: sharp acid, more full-bodied Body, dry feeling.

However, it was found that the extraction rate of espresso with pre-immersion extraction was not higher than that of espresso without pre-soaking. When the coffee is presoaked within 10s and 15s, the extraction rate P value is less than 0.05; the espresso extracted with 10s or 15s low presoaking will actually bring lower extraction rate. The P values of espresso extracted by 5 s pre-soaking or 30 s pre-soaking extraction were all above 0.05.

Therefore, the experiment basically points to the conclusion that there is no obvious evidence that pre-soaking will lead to a higher extraction rate of coffee.

"pre-soaking" may not produce a higher extraction rate, but it helps to improve consistency and reduce errors. From the taste observation, it can be felt that pre-soaking can counteract the bad and imperfect espresso extraction technology, although the extraction rate is not high, but the taste of these coffee will be better. The pre-immersion technique helps to minimize the scope of errors and to extract any inconsistencies or errors in the preparation process prior to the preparation.