On the production process of espresso there is water in the powder bowl after coffee extraction

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SCA espresso ESPRESSO parameters:

Powder quantity: 7g powder above water temperature: 88 ℃-96 ℃ pressure: 9-10 bar extraction time: 20S--30S extraction quantity: 30 ML ±5 ML (including crema)

Espresso has different portions, one shot,2, one shot,3, one shot.

The size of the Italian filter cup determines the amount of powder, whether single or double, first we need to weigh the powder, here is a small detail, there are two concave lines in the powder bowl, and the concave line here is the position of the cooking head in the filter when the handle is locked.

Do not exceed 02 this concave line as the principle, the amount of powder will also affect the concentrated extraction, usually I will extract 40 grams of espresso from 20 grams of powder to start making coffee.

Our general extraction time is about 25s. After weighing and pressing the powder, we begin to extract by machine (after each filling and pressing, please pay attention to whether there is a gap around the powder bowl and try the inverted powder bowl. Just see if pressed powder will fall off).

Details: before buckling the handle to cook, you will first put some water off the front end, and then install the handle to start the extraction; electronic scale: when you put the coffee cup, you can put an electronic scale under the coffee cup. Heavy coffee can also help you maintain stability.

Timer: calculating extraction time

The first stage of extraction (4 ~ 6 seconds)

Moisture has just come into contact with coffee powder, pressed powder is still strong, so the resistance is still very high, and the channel is only on the side of pressed powder, we will find that the flow shape is small and thick at the top and thin at the bottom.

The coffee liquid in the front section shows the most primitive dark brown of coffee.

Middle stage of extraction (12-14 seconds)

With the inward extraction of water, the external coffee particles can absorb water and expand because they have been in contact with water for a long time. The flow pattern will widen as the channel becomes larger, showing a maximum velocity during the period of 12 to 14 seconds. Slowly continue the extraction, the coffee liquid in the extracted area will turn to ochre red, while the newly extracted coffee liquid will still be dark brown, so there will be two colors of coffee liquid in this state.

The last stage of extraction (21cm 23 seconds)

Near the end of the extraction, during the period of 21-23 seconds (depending on the coffee beans), each coffee particle expands with full water, coupled with the reduction of extractable matter, so there will be a phenomenon of flow shrinking. When the extraction reaches the end, the substance that can be extracted from the coffee powder is greatly reduced, and the coffee liquid will be golden yellow. After that, the golden coffee liquid will become more and more, and finally become white or transparent.

In the process of Italian extraction, there are three stages of flavor changes: the first stage will have rich fruit flavor and aroma with high acidity; the middle stage will be sweet, nut, cream and caramel flavor; and the latter stage will show bitter and miscellaneous taste.

The first two segments are good flavors, but the sour in the front and the sweetness in the middle do not necessarily blend well, so we need the bitterness of the end to dilute their flavor so that the espresso can get an overall flavor balance.