Coffee Extraction Formula and Gold Cup Extraction Theory| Discussion on the relationship between extraction rate and water-powder ratio

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Let's start with SCAE's gold cup extraction theory.

According to the definition of SCAE (European Coffee Association), Gold Cup Standard (published in 1960)

"Coffee is brewed with 1000ml water, 50m / m / 65g coffee powder, 92 °C-- 96 °C hot water."

Basically, SCAE decided on a strike zone.

That is, the part of the middle gray line.

Then let's give an example to illustrate.

Suppose the extraction rate is 18%: the concentration of 1.45% is the green point in the picture.

I'd like to make 240 grams of coffee. How many grams of powdered coffee should I use?

240 * 1.45% = 3.48g (coffee extract)

3.48g / 18% = 19.3 (19.3 grams of coffee powder should be used for brewing)

Of course, there should be some differences in the extraction ratio of different kinds of coffee beans

But basically, the difference should not be too much beyond this frame. In terms of the ratio of water to coffee, the green point is about 12.4.

So write down the ratio of water to coffee powder suggested in the selected / best series below.

For your coffee lovers' reference, it is also roughly in line with the SCAE Golden Cup principle.

Medium baking / medium and deep baking selection series 12:1-17:1

Light baking / shallow medium baking best series 10:1-15:1

(the shallow baked bean BODY is thinner and the concentration can be increased to achieve a stronger taste.)

The times are advancing rapidly.

At present, the SCAE traditional gold cup extraction principle can only be said to be a basic principle.

92Murray 96C proposed by SCAE in 1960.

In fact, it is not fully applicable to such a diverse method of cooking today.

But the most popular principle (the frame above) still exists.

In other words, how to score the strike zone at different water temperatures is the direction that can be considered at present.