A single serving of espresso is commonly referred to as "1 shot"! A shot is a type of wine measurement. 1 shot is equivalent to 1 ounce, which is around 30ml. 9-11g of ground coffee is used to make one shot of espresso. This parameter is now rarely used. The Single Serve Concentrate Bowl is to blame for this.

Single-serve Espresso Basket

Friends who have interacted with semi-automatic coffee machines are likely familiar with the double-serve espresso basket. The extracted powder cake is similarly a typical "round almond cake," and the powder bowl's volume has a columnar shape.

The single-serve espresso basket has an upside-down cone form. The upper part of the roughly two-layer construction is the same caliber as the double-serve espresso basket. The lower half layer is intended to be narrower in order to retain the same surface diameter and the same maximum thickness of the powder layer, despite the fact that a single-serve espresso basket contains half as much powder as a double-serve espresso basket.

The single-serve esresso basket, however, was not as straightforward in the extraction trials on Front Street as the other half of the double-serve espresso basket.

In 27 seconds, 40g of coffee liquid are extracted from 20g of powder using double powder bowls. The measured concentration is 10.48%, and the estimated extraction rate is 21.72%.

A single espresso basket is used to extract 20g of coffee liquid from 10g of coffee powder at a moderately quick flow rate of 22 seconds, 8.83% concentration as measured, and 18.38% extraction rate as estimated. Both of them are pretty dissimilar.

You can only finely grind the powder or use more of it if you want the single-serve powder bowl's output to resemble that of the double-serve powder bowl. Coffee shops cannot grind products to their specifications, and increasing the amount of powder would result in higher costs and unpredictability.

It needs to be increased to 12.5g of powder, according to Qianjie's testing, in order for the concentration to be close to the results of the double powder bowl.

Why is the difference so great?

Structure is the foundation of everything. The straight and cylindrical structure of the double-serve espresso basket ensures that the force of each portion is uniform and that the extraction, whether pressed powder or pressurized, is reasonably uniform.

The single-serving espresso basket sacrifices the bottom structure in order to maintain a uniform caliber (so that it can fit the brewing head) and ensure the thickness of the powder layer at the same time, so that the pressure around it is always higher than that in the center of the same level, whether it is pressed powder or pressure extraction. pressure. When the powder is squeezed, the surrounding area will be denser than the center. Water in the upper half layer and the center will penetrate faster than water in the surrounding areas during extraction, but water in the lower half layer will flow into the center, resulting in uneven extraction. A channeling effect exists.

Although a single-serve espresso basket and a double-serve will be given, the single-serve one is usually directly sealed back into the shipping box. It is now increasingly advised that the espresso extracted from the double espresso basket be one espresso, with a powder-to-liquid ratio of 1:2.

Reference: kafeigongfang, makecoffee.cn