Coffee extraction principle: to explore the effects of various factors in coffee extraction on coffee flavor.

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Espresso Coffee extraction detailed steps Italian concentration common sense

It was supposed to go straight into implementation mode.

But if you think about it, you'd better bring this article to the front first.

In this way, you may have a general understanding of the different cooking methods.

It is also easier to clarify the relationship and causes of different flavors.

* this article will discuss more rational ideas that those who do not like to be careful--

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The relationship between the thickness of grinding was mentioned in classroom 4.

A very important variable-time is also mentioned in the article.

The extraction of coffee is nothing more than two things: "solubility" and "diffusion".

The longer the time, the more molecules dissolved, the more complete the diffusion.

Of course, you must think of another variable: temperature.

The higher the temperature, the higher the activity of the molecule.

The solubility increases and the diffusion accelerates.

But everything has a limit.

The longer the time, the higher the temperature.

We have to find a balance between this.

For example, when playing tennis, you have to let the ball hit the sweet spot of the racket net (sweat point)

It's not bad if you miss it, but it just doesn't feel good.

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Back to the dissolution rate--

The process of making coffee is

Dissolve thousands of chemicals in coffee, such as aromas, oils, caffeine, and so on, into water.

And in this pile of matter,

Not everything is pleasant.

The first half of coffee extraction (strictly speaking, only 20% of the extraction rate)

Is rich in aromatic substances, coffee oils and other caramel reaction crops

And the smell behind it.

Most of them are astringent wood.

So it's not "high solubility" or "complete extraction" is a good thing--

How to effectively extract the front segment and reduce the influence of the taste of the latter segment

This is the direction that every coffee maker is working on--

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Just like I used to do a chemical experiment.

To analyze the role of a variable.

All other factors must be controlled at a fixed value first.

Only in this way can the result be of reference value--

We can sum up several trends:

1. The finer the coffee powder is, the larger the contact area is and the faster the extraction speed is.

two。 The longer the extraction time, the higher the solubility.

3. When the temperature is higher, the solubility is higher, the diffusion is greater, and the extraction speed is faster.

If you use the hand bubble type, add one more item.

4. The faster the flow rate, the lower the concentration.

If semantic condensation is used, then

5. When the pressure is higher, the solubility is higher and the extraction speed is faster.

For the time being, the evaluation of taste will not be taken into consideration in this part.

Suppose the extraction rate we require is fixed at 20%.

Fix a way of cooking, such as syphon

Then the factors that we can adjust are reduced to powder size, extraction time, and water temperature.

If the temperature control is accurate

We can experiment to find out how long it takes for each of the grinding scale 1 and scale 3 to achieve the same extraction rate.

And on this same benchmark,

So that we can add the sense of taste to compare which of the two extraction methods has the best flavor.

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You might say: what flavor does the same extraction rate compare to?

The same extraction rate represents the same weight of the total substance dissolved from the coffee powder.

But it doesn't mean that the dissolved ingredients are equal by weight--

So if you keep focusing on the number of extraction rate, you may get into a misunderstanding.

The same is true of TDS (Total Dissolved Solids)

This does not mean that the extraction rate is meaningless to TDS.

The meaning of these two numbers is that the structure is almost the same under similar cooking conditions.

A quantitative reference value of trace difference

Speak a little vernacular.

Is when you use the same way of cooking.

The same thickness of powder and the same cooking time.

Just adjust the temperature of the water by 3 degrees--

Under the condition of such slight difference

To calculate and measure the value will be related to the flavor.

But it's only the difference of "which one tastes better".

It won't be "this cup and that cup of garbage".

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Back to the level of taste--

Are these factors only related to the extraction rate?

Of course not!

Coffee is actually very delicate.

Even a slight adjustment may change its flavor.

Fine ← particles → coarse

Rich ← flavor and clean →

Short ← time → long

Light ← flavor → thick (excellent)

Monotonous ← flavor → miscellaneous flavor (lack)

Low ← temperature and high →

Acid ← flavor → bitter

Slow ← flow rate → fast

Rich ← flavor → clean (excellent)

Mixed flavor ← flavor → monotonous (lack)

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These are simple dichotomy.

Each variable has its own advantages and disadvantages.

Except for everyone's personal taste.

The characteristics and baking degree of beans should also be taken into account.

To find sweat point--.

To brew a satisfactory cup of coffee--

.