How to extract a cup of perfect espresso how to make the principle of Italian concentrated extraction

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Extract the six gold elements of a perfect espresso

Extraction pressure: 9 bar (atmospheric pressure)

Extraction time: 25 sec (s)

Extraction quantity

Coffee cup temperature

Extraction water temperature

Temperature after extraction

Note: extraction pressure: 9bar is the best option, pressure is not the greater the better, so today's coffee machine, many 15bar will be adjusted back to 9bar (commercial is also 9bar, commercial coffee machine pressure gauge, or even 14: 15 bar is a red hazard warning)

Where all the achievements and quintessence of coffee production lie, precision design and coffee machine manufacturing play an important role in the production of espresso.

1. Pump pressure: the pressure at the outlet of the loaded bubble head is measured as

two。 The water temperature injected into coffee powder is 88 degrees Celsius, with a positive and negative error of 2 degrees Celsius.

* beyond this temperature: coffee can be said to be "burned": it burns off its aroma and taste-bitter, dark crema, and the foam almost disappears.

* if the temperature is too low: coffee can be said to be "underextracted": coffee is light, tasteless and undurable, and crema is not thick enough.

Water quality

Water is the main ingredient of coffee, and for this reason, we cannot ignore this important ingredient. Scale is formed by the crystallization of calcium and magnesium ions under thermal catalysis. Today, there are specific tests that can detect the content of calcium and magnesium carbonate in water. This test is "hardness coefficient of water" or "KH".

Coffee beans

Bakers choose coffee beans according to origin and variety to ensure consistent quality. Roasting technology can directly affect the taste of coffee.

* shallow baking: slightly sour and less bitter

* Deep baking: less sour and bitter

Bean grinder

The bean grinder is an important foundation for making a good cup of espresso. It is an indispensable tool for the coffee machine, which determines the quality of grinding. Coffee grinding should be so fine that the average flow time of two cups of espresso is 25-30 seconds.

1. If the grinding is too fine, the flow time of the two cups can be as long as 35-40 seconds, when the coffee can be said to have been overextracted: dark unstable foam appears-the coffee is too bitter.

two。 If the grinding is too rough, the flow time of the two cups is only 20 seconds, and the coffee can be said to be "insufficient extraction": the color is too light, the foam is too little-insipid.

Coffee cup

Enjoy espresso itself is an art, in the use of utensils should not be rash, in order to show the advantages of coffee. Coffee cups used to hold espresso should be stored at a temperature of about 40 degrees Celsius, a thickness of 2-3mm, a height of 5-6cm, a maximum diameter of 5cm and a capacity of 70ml, and should not be poured to the edge of the cup under any circumstances.

What is pre-immersion?

In the process of coffee extraction, the hot water injected with 10--15cc is immersed in the coffee powder for about 3-5 seconds; let the coffee powder soak first, and then enter the extraction process; in this way, the CREMA extraction will be more complete and smooth, and the taste will be better; the coffee will be more layered (taste)