Espresso espresso technology

Use the same amount of beans as a single espresso, which is 1 stroke 2 of an espresso. It can be said that it completely crushed the delicious essence of coffee beans. (Ristretto) in Italian, it means concentrated, short, material: 1 cup (15-20ml) Espresso coffee beans 6.5m / 10g coffee beans (6.5m / 10g), extraction time (20m / 30s, water temperature around 90 degrees Celsius) are all the same as a single espresso, the amount of extraction will vary slightly from barista to barista. Roughly half the amount of So'o, that is, 15-20ml, my approach is to use 8.5 Solo 9 g of beans for 27 seconds and 28 seconds, and the extraction amount is about 17ml. The grinding thickness of beans is even finer than that of Solo.