One of the golden cup theories of coffee: why is the extraction rate up to 18% Murray 22%?

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Today we are going to discuss coffee's so-called "Gold Cup" theory. Some people don't like the golden cup theory because the name seems to imply that as long as it meets this standard, it is "delicious coffee". In fact, I quite agree that coffee that does not conform to the golden cup theory tastes good, but it is a bit strange to say that we can ignore the golden cup theory at all. Maybe it's called "extraction theory". Maybe we don't have any opinions. In fact, what we want to talk about is extraction.

When coffee beans are ground into coffee powder, not everything can be dissolved in water. No matter how hard we try and how violent we are, we can only extract up to 30% at most. But this 30% contains flavors we don't like, so most coffee people will probably agree that our goal is to extract 20%. If we consider the capacity up and down a little bit, it will be about

18%-22%

Is an acceptable range. So, no matter what method we use to make coffee, hand brew, race wind, or even espresso, the final goal is an extraction rate of 18%-22%.

You probably know how to improve the extraction rate of coffee with your feet (on the contrary, you know how to reduce it). Here are a few ways to improve the extraction rate:

Increase the temperature of cooking water

Grind the beans a little bit

The cooking time is prolonged.

Stir harder.

Anyway, the target is 18% Mak 22%. Every time you make coffee, you find a way to pull the extraction rate to this range, that's it, this is the focus of golden cup theory.

What? No more?

What I really have to say is really like this. But you should have a problem, that is, we made coffee, how do we know the extraction rate? Unexpectedly, this seems to be a very simple question, which is the beginning of all the trouble.

What the extraction rate is is easy to explain. We want to know how much coffee powder got into our coffee, of course.

Coffee extract = weight of coffee powder before brewing-weight of coffee powder after brewing

And then the extraction rate is

Extraction rate = coffee extraction amount / weight of coffee powder before brewing

Remember (again), this number is between 18% and 22% and you go to heaven, which is called "insufficient extraction" less than 18% and "overextraction" more than 22%. Is there a problem with this? Okay, no problem, we'll just go up here... What? There's a problem? Where there is a problem, the weight of coffee powder before brewing is of course measured before brewing (remember to strictly say "ground" weight, but we'll talk about it later). The weight after brewing is of course the weight of coffee grounds after soaking.

Wait, did you find out the smart one? Coffee grounds are actually finished coffee powder, plus some water attached to it. What if we just want to know how heavy the rest of the coffee powder is? It's very "simple". Just find a way to make it dry and measure it later. So, in the past, people came up with a great one.

"oven drying"

Every time you make coffee, the leftover coffee grounds are dried, dried and then weighed.

That is, you make a cup of coffee, probably wait for the oven to bake for you, you measure it again, take out the computer and press it, and finally … What, the extraction is a little high? So you adjust it again, flush it again, dry it in the oven, and count it again. What? It's too low... At this time, I think a sane person will not want to do the whole process again.

So, we're going to think of something else. Now we just need to remember one thing: the goal of any coffee brewing is to achieve an extraction rate of 18%-22%.