What is the right extraction time for espresso machine? Requirements for standard espresso

In brewing coffee any coffee, there is one parameter that cannot be avoided, and that is the extraction time. Espresso is more time-sensitive than other ways of making it.

This is because the extraction time of espresso is relatively short, and the gap varies greatly from second to second. Therefore, the extraction time is a very important parameter for espresso.

Generally speaking, we think that when other parameters are constant, the shorter the extraction time is, the less coffee substances are dissolved, and the longer the extraction time is, the more coffee substances are dissolved. If you have known the golden cup theory, you should know that the coffee substance is not dissolved as much as possible, but there is a moderate range. In some very old espresso textbooks, one espresso is extracted with 7-9 g of powder to extract about 1 ounce of espresso, while the double concentrate is extracted with 16-18 g of powder using a shunt handle to extract 2 cups of 1-ounce espresso. No matter it is single or double, the extraction time is within 20-30s.

Of course, few people should copy this extraction formula completely now, because times have changed. One of the most obvious features is that the quality of coffee beans has been improved, the degree of roasting is not as deep as before, and the coffee has become "resistant". Copying the previous formula is not good.

The current espresso extraction standard has more stringent requirements than before: 1) a double powder bowl is used as the extraction unit of espresso; 2) the espresso liquid is calculated by weight rather than by volume; 3) the ratio of coffee powder to coffee liquid tends to be 1: 2) the extraction time is more inclined to 25-30 seconds. Therefore, under the current extraction parameters, the fastest way to debug espresso is to fix the ratio of powder to liquid at 1:2 and to control the extraction time at 25-30 seconds by adjusting the degree of grinding and the amount of powder. Through the data of extraction time, we can also know the general trend of the flavor of espresso. For example, espresso may tend to be thin, light and sour for less than 25 seconds. If the time is more than 30 seconds, it may tend to be bitter and exciting. Time is also an indicator of the stability of your recommended extraction scheme. For example, we are debugging an espresso parameter that we think has a good flavor, and then we will use this parameter to extract 2-3 cups continuously. If the time error is within 1 second, then this parameter is considered stable. If the time error is more than 1 second, then you need to adjust the parameters again.

Some friends may also ask: "does qualified espresso time have to be within 25-30 seconds?" Not necessarily, as suggested by Qianjie, the time for hand-brewing coffee is 2 minutes, which does not mean that 2 minutes and 30 seconds of coffee is not qualified. More depends on the whole extraction parameters, for example, the increase in the amount of powder will lead to a relative extension of the extraction time; the pre-immersion extraction time will also be included in the extraction time, so the use of pre-immersion extraction time will be extended accordingly.