Research on Fine Coffee extraction: what is the Coffee Gold Cup Theory Gold Cup extraction rate Table

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The Gold Cup coffee ratio defined by the scaa American boutique coffee association and the scae European boutique coffee association must hold the extraction rate of coffee at about 20%, while the TDS is about 1.1% to 1.3%.

For Drip Filter drip cooking, how to extract the best coffee flavor is controlled by two variables: the extract of coffee powder and the concentration in a cup of coffee, and these two variables had the so-called "Coffee Gold Cup" golden cup coffee theory as early as 1960.

According to the definition of Gold Cup Standard by SCAE (European Coffee Association): "Coffee is boiled with 1000ml water, 50g coffee powder, 92 °C ~ 96 °C hot water". The coffee cake is boiled at the "bull's-eye" position of the optimum extraction rate (Extraction) and concentration (Strength Concentration), that is, "Gold Cup".

First of all, each coffee can be extracted, the maximum is about 30% (that is, 70% of xylem cannot be extracted), that is, 10g coffee powder has up to 3G coffee soluble extract, while a cup of delicious coffee, the best extraction rate of coffee, that is, 60% 70% of the maximum soluble matter of 30% coffee is the most suitable extraction, which is less than 60% (less than 18%). The coffee flavor will show incomplete flavor. On the other hand, if the extraction rate is more than 70% (the extraction rate is more than 22%), the coffee will be overextracted and the coffee will show bitter, spicy and bad taste.

Therefore, the best extraction rate of coffee is 18%-22%.

This 18% 22% 30% * (60% 70%), that is, the maximum extractable rate of coffee is 30%, and the best coffee flavor is 6% 70%. Why don't I just write 18% 22%, but around 60% 70% of 30%? when we are brewing a cup of coffee, we can imagine how to extract the best flavor of 60% from the maximum extract of coffee.

In other words, 10g coffee powder can extract up to 30% (3G) of coffee soluble matter, but we expect the best extract 18%-22% (1.8-2.2g).

In addition, how much hot water these extracts will dissolve in, this is the coffee concentration, the optimum coffee concentration is between 1.0 and 1.5%, less than 1.0% light and tasteless, it is better to drink boiled water, if the coffee concentration is too strong more than 1.5% (for dripping coffee), it's not a good taste. The best Gold Cup concentration of dripping coffee is 1.2%-1.45%. Too light or too strong coffee concentration is not good taste. American flavor: coffee with a relatively light concentration, so the TDS of a cup of American coffee is about 1.2-1.3%. European flavor: generally speaking, the concentration of European coffee is a little stronger, so the TDS of a cup of European coffee is about 1.3 to 1.45%.

Therefore, SCAE (European Fine Coffee Association) defines the target position of the standard Gold Cup, which is related to the extraction rate and concentration, that is, the amount of coffee powder is as follows:

Minimum and maximum booking bubbles

Coffee quantity ml coffee powder quantity g

240 13 18

300 16 23

360 19 29

400 21 31

500 27 38

600 32 46

800 43 62

1000 54 77

From the control table to determine the amount of coffee to order and set the upper and lower limits of coffee powder, how to reach the best extraction rate from 0: 30% to 18: 22%, and the concentration of coffee is just at 1.2%-1.45%, just like how to throw a good ball. After brewing a cup of Gold Cup coffee, the above-mentioned basic powder quantity and bubble quantity are determined, whether it can reach the best extraction rate of 18%-22%, while the concentration falls to 1.2%-1.45%. It involves the problem of extraction rate, grinding thickness of coffee, water temperature, filter medium (affecting water retention time). Wait for mutual cause.