The function and characteristics of pre-soaking Italian Coffee do you need steaming to make Italian concentration

Steaming is a very important process in hand-brewed coffee. It is no exaggeration to say that if you cancel the steaming step, it will add a lot of uncertainty to the hand-brewed coffee, and it may be difficult for even brewers to predict the flavor direction of the coffee.

Some friends are curious that the steaming of hand-brewed coffee has such a great impact on the final flavor of coffee, so does Italian coffee also need to be steamed?

In fact, espresso does not steam this step, because when the espresso machine is used to extract coffee, the coffee powder is pressed into a dense pressed powder and then "pressed" into a thick liquid under the water pressure of 9bar. So espresso is famous for its stable extraction. For example, the classic espresso extraction scheme heard before is to extract 1 ounce of coffee liquid within 20-30 seconds. In theory, as long as the amount of powder, liquid and time are stable, the taste of espresso can be stable. However, with the diversification of roasting degree of coffee beans used in espresso and the pursuit of freshness of coffee beans, the extraction of espresso is no longer so stable. For example, the previously used espresso beans were kept for as little as half a month and as long as one month. The active gas in the coffee bean body is basically emitted, and the state change of the cultivated coffee bean is not obvious, so the performance of the extraction is very stable.

Now in order to reflect the freshness, the time of growing beans has been shortened, it is possible that when extracting, the carbon dioxide in the beans is still relatively rich, so the extracted oil is relatively rough and the extraction is unstable.

As a result, it is becoming more and more popular to add the "pre-soaking" stage when extracting espresso. Pre-immersion extraction is in the buckle on the cooking handle, first start no pressure to release water, wet pressed powder, wait for a period of time before the formal pressurized extraction. It can be understood as the "steaming" of espresso. The effect of pre-immersion is also very obvious, the first point is to discharge active gas. Just like coffee beans with insufficient cultivation time, overactive carbon dioxide will affect the stability of coffee extraction, so pre-soaking before formal extraction and removing this part of carbon dioxide first will not hinder the subsequent extraction.

The second point is to reduce the probability of channel effect. The water pressure of 9bar is very strong, if the filling of pressed powder is not uniform, then the water column can easily break through the weakness and form a channel effect. And first carry on the pre-soaking stage, let the coffee pressed powder expand after absorbing water, so that the pressed powder is more dense, thus reducing the channel effect.

The third point is the application of pre-soaking, so that the scheme of Italian extraction is no longer single. For example, in the past in the extraction of coffee, there is a sharp acid situation, the only way to adjust the grinding degree, or adjust the proportion. Now it is also possible to use pre-soaking to improve the efficiency of subsequent extraction. The premise of using pre-immersion is that the coffee machine itself supports the function of pre-immersion, some machines can set a pre-immersion extraction, some machines need manual pre-immersion. If you are also in a manual state, you can judge the water cut-off time by observing the liquid point, for example, the front street is observed through a bottomless handle, and the coffee liquid oozes from the bottom in about 3-4 seconds, then you can cut off the water for pre-immersion in the third second.

There is no standard answer to the question of how long it takes to pre-soak before formal extraction. It can be soaked for 5 seconds, 10 seconds, or even 30 seconds. It depends on the cultivation of coffee beans and the flavor performance of the parameters such as grinding degree and ratio.