Introduction to the Theory of extraction rate of hand-brewed Coffee Gold Cup Teaching techniques for calculating the extraction rate of hand-brewed coffee

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/Gold Cup Theory of Coffee/

We now begin the practical operation, first discussing the extraction rate calculation of the manual method.

Some people may wonder why we have to discuss extraction rates according to different brewing methods.

Standards are important in the coffee world. It acts like a yardstick, giving the coffee white a good reference point for beginners.

All coffee experiments and bar products of Qianjie Coffee are based on the Gold Cup Theory.

However, this is only a reference and does not mean that it is completely correct.

Qianjie believes that if coffee has been extracted to the "golden cup" interval, but the taste and flavor of drinking is not how,

At this time, we do not have to copy the theory ~ appropriate improvisation can allow guests to drink their favorite coffee in the front street is enough.

Qianjie believes that whether it is produced in stores or to participate in competitions, we hope to develop our own brewing methods.

Let each coffee show its own uniqueness.

So we need to understand the taste of different coffees, and we need to understand what happens to them at different stages of extraction.

What is the difference between its concentration and taste? All of the above are very important things.

Coffee beans are not all soluble in water, only 30% of the substance in a coffee bean can be dissolved in water,

The remaining 70% consists of insoluble substances such as wood fibers.

Therefore, the maximum extraction rate of coffee is only 30%. Among the substances soluble in water,

Some of them don't want to be in the final coffee. (Good riddance.jpg)

The so-called extraction rate refers to the proportion of coffee substances dissolved in water to the total coffee powder involved in the extraction: i.e. Weight of dissolved coffee substance/weight of raw coffee beans (powder)= extraction rate

How? Are you feeling dizzy? Let's keep going down!)

Take a chestnut:

If 15 grams of coffee powder is used for brewing, then the coffee grounds are completely dried, and then the weight is 12.3 grams.

The weight of the substance dissolved in water is 2.7 grams. The extraction rate of this cup of coffee is 2.7÷15=0.18 (18%)

The extraction rate calculation method we often use is related to coffee concentration.

Of course, to do this, we must first prepare an instrument to detect the concentration (TDS detector).

/Concentration vs. Extraction Rate/

[Concentration] indicates the proportion of "extracted coffee substances" in a cup of coffee.

[Extraction rate] indicates the proportion of "extracted coffee substances" in the total coffee bean weight.

(One body is coffee liquid, one body is coffee beans or coffee powder)

The most famous gold cup extraction criterion is the gold cup extraction diagram

The subscript axis indicates the extraction rate of coffee powder, the left-hand axis indicates the concentration of coffee solution, and the diagonal line indicates the powder-water ratio (powder amount/water amount).

According to these conditions, we know: coffee concentration = weight of coffee substance extracted/weight of coffee extract = weight of coffee substance extracted/weight of coffee beans (powder)

Then the formula for calculating the coffee extraction rate obtained by combining the above formulas is: Coffee extraction rate = coffee concentration × coffee weight ÷ coffee bean (powder) weight

However, it should be noted that drip coffee because the coffee powder itself will absorb twice the amount of water, so the coffee liquid weight = water injection-2 × coffee beans (powder) weight

Take a chestnut:

If 15 grams of coffee powder is used to brew coffee in a 1:16 ratio of powder to water, the concentration measured by the concentration meter is 1.37%,

Then the extraction rate of this coffee is 1.37%× (240-2×15)<$=19.18% The front street is based on this range to standardize our brewing parameters.

Every time a new bean is put on the shelf, it will undergo adjustment of baking, cup test, hand flushing and other links, among which the adjustment direction of hand flushing is to see the TDS concentration. If you only drink coffee at home, you don't have to spend a lot of money to buy a special instrument (cover your face.jpg), according to your taste to judge the shade.

Front Street·Yanshen Reading

Different countries have different gold cup extraction criteria, the following are the coffee bean extraction standards of each country:

Specialty Coffee Association of America (SCAA)

Extraction rate [18%-22%] Concentration [1.15%-1.35%] European Fine Coffee Association (SCAE):

Extraction rate [18%-22%] Concentration [1.2%-1.45%] Norway Coffee Association (NCA):

Extraction rate [18%-22%] Concentration [1.3%-1.55%] Brazilian Coffee Association (ABIC):

Extraction rate [18%-22%] Concentration [2%-2.4%]

As can be seen from the above, different countries have different definitions of the Gold Cup criteria, and the concentration requirements of coffee in different countries are different.

However, the only certainty is that it is generally believed that the coffee extraction rate is 18%-22%, and the extracted coffee substance is more delicious.

What is over-extraction?

This kind of situation believes that everyone has encountered, after tasting a mouthful of coffee, say "bitter, this cup has been extracted!"

Qianjie believes that suffering is not exactly equal to excessive extraction.

Despite the differences in sensitivity to bitterness, even when coffee is unusually burnt and bitter,

You can't put all the pot on the "over-extraction".

First, the term "over-extraction" is based on the Golden Cup, i.e., the extraction range beyond the Golden Cup criteria.

The Gold Cup criteria consider that coffee extraction rates in the range of 18-22%, the extracted coffee substances are more delicious;

More than 22%, it is possible to extract unpleasant bitter flavor substances.

Therefore, over-extraction essentially describes coffee with an extraction rate of more than 22%.

Coffee with a general extraction rate of more than 22% will show a bitter taste,

Over time, they equated suffering with excessive extraction.

This extraction rate also applies to hand-brewed coffee. Then, Front Street Coffee will demonstrate Ethiopia's Flower Queen 4.0.

You need to prepare the following items: make a cup of hand-brewed coffee, coffee strength tester (Extract Mojo), titration tube, water. Front Street·Ethiopia Sidama Flower Kui 4.0 Coffee Bean

Country: Ethiopia Fiscal year: 2003 Production area: West Damo Altitude: 2250-2350m

Breed: Native species Treatment: Solarization

Flavor: Rose, strawberry cream, citrus, passion fruit, oolong tea

Qianjie·Brewing Scheme

Powder: 15g

Powder water ratio: 1:15

Grindability: fine grinding (80% pass rate for No. 20 standard sieve)

Water temperature: 90 degrees

Filter cup: V60

Qianjie·Brewing Experience

In the first stage, 30 grams of water was injected and steamed for 30 seconds.

The second stage is injected with 95 grams (electronic scale shows about 125 grams), which is completed in about 1 minute, with an interval of 10 seconds.

In the third stage, the remaining 100 grams were injected (the electronic scale showed about 225 grams), and the injection was completed in about 1 minute and 40 seconds.

After about 2 minutes, remove the filter cup and complete the extraction.

How to determine coffee strength?

·Calibrate the concentration tester first and clear the standard with pure water;

·Stir and cool the freshly extracted coffee solution, extract the coffee solution with a titration tube, and put it into a coffee strength tester, at this time the temperature must be reduced to room temperature;

·Press the Measure button and try to measure the value several times until the value stabilizes.

Front Street Coffee assumes that the water absorption of coffee powder is 1:2,

So we get roughly 225-(15×2)=195 grams of coffee, and the measured concentration is 1.45%,

Then the extraction rate is 1.45%×195÷15=18.85%

From this, it can be concluded that this cup is a hand-brewed coffee with a concentration of 1.45% and an extraction rate of 18.85%.

Therefore, it can be judged that this is a cup of hand-brewed coffee with high concentration and moderate extraction rate, and other factors such as this data and proportion can be used to adjust the coffee extraction concentration.

Of course, the Gold Cup is just a system to provide reference. After all, everyone's taste is different.

Hand brewed coffee that matches the Gold Cup data does not necessarily mean good coffee,

Therefore, it is recommended that everyone try more coffee in front of the street. Drinking more is the recommended practice.

In addition, the ratio of hand brewed coffee powder to water also affects the extraction of coffee concentration very much. If the ratio of water is too large, the extraction concentration will be insufficient, and there will be no atmosphere when drinking.

On the contrary, if there is less water, it will be over-extracted, and the coffee will become bitter and difficult to drink. Therefore, Qianjie Coffee also determines the powder-water ratio of hand-brewed coffee through hand-brewing practice. Then share it with everyone below!

/Hand brewed coffee·Powder water ratio/

As mentioned above, according to the extraction theory of sca gold cup, the extraction parameters of hand-brewed coffee water powder ratio are as follows:

[Heavy Flavor] 1:10~1:11, i.e. 1:12.5~1:13.5 of Gold Cup Standard

[Moderate Flavor] 1:12~1:13(i.e. 1:14.5~1:15.5 of Gold Cup Standard)

[Small Fresh] 1:14~1:16(i.e. 1:16.5~1:18.5 of Gold Cup Standard)

the gram ratio of coffee beans to brewing water is 1:14.5 - 1:15.5;

It is easy to reach the gold extraction rate of 18%~22% and the gold concentration of 1.15%~1.35%.

This is why Front Street Coffee always recommends brewing at 1:15.

This parameter was determined because it had been validated several times before. Although 1:12-1:15 is a suggested range,

Front Street Coffee also experimented with a few parameters that were no longer in the range.

1:20 this powder water ratio drip coffee taste is very clear, 1:10 will be very strong;

By adjusting the test, 1:15 is the front street coffee that is considered more suitable for brewing most coffee beans.

After determining the ratio of powder to water, determine the amount of powder.

Front Street Coffee is 15 grams of powder for one person and 225 grams of water for one person.

The above is the relevant content of the front street coffee finishing related to the standard water powder ratio of the hand brewed coffee cup extraction

Of course, some friends like to use 1:14 or 1:17 and so on, these are OK, the key depends on whether they can accept. Front Street Coffee provides only a parameter acceptable to the public, which can be used for reference.

Hope to help coffee lovers understand more about the content.

More fine coffee beans, please add private WeChat Qianjie Coffee, WeChat: kaixinguoguo0925