What is the effect of steaming hand coffee without swelling or steaming? What is the meaning of hand dull steaming?

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What benefits will steaming bring to extracted coffee?

Let's first observe the expansion of the following steaming, in fact, it can also help us to detect whether the coffee beans are fresh or not!

More importantly, the coffee particles after the coffee powder is discharged during steaming can be discharged and absorbed more evenly, which can make the coffee extraction more uniform.

During steaming, the air between the coffee powder particles expands and releases a large amount of carbon dioxide, while a short gap layer appears between the coffee powder particles, which can provide more space for the hot water to pass through the powder layer during formal water injection.

And if the initial step of hand flushing is less steaming, the extraction time will be longer, which may lead to excessive extraction, because the extraction time is longer, the dissolved substance is more, the taste may be more sour and irritating, or the mouth may be full of smells.

How to control the steaming process?

Before steaming with water, make sure the coffee powder is as horizontal as possible in the filter screen or filter paper. We should pay attention to the control of the flow rate at this time, the force of water injection is not too large, try to be gentle.

The amount of water used in steaming should be 10% of the total water. For 240 milliliters of coffee, the amount of water needed for steaming is about 24 milliliters. The amount of extract flowing is as little as possible; when there is too much extract in the pot, the amount of water injected should be reduced, or attention should be paid to the degree of grinding.

Steaming is about 25 to 40 seconds (depending on the degree of grinding and baking). When the expansion of the coffee powder surface is over and the surface is about to shrink, it represents the completion of steaming.

In an ideal steaming process, the coffee powder will slowly expand in the presence of hot water, as if the coffee powder keeps pushing the hot water to the top. And the best time for the end of steaming, when the surface is about to shrink, is a good time to start the first water injection.

For hand-made coffee

Every step will change the original flavor.

If there is any confusion, we will correct it from the beginning.

Friends who want to make just the right drink.

Combine the previous knowledge points to brew it together!

Some people say there is no need to be bored.

Some people say they want to be bored.

It makes everyone's heart depressed.

I don't know how long it will last...

And how boring it is.

So. Take advantage of this opportunity... Let's talk about the magic stick.

First of all... The lower the current, the softer the better.

Because just to get the coffee powder wet...

The current is too high and too strong. As soon as it rushes up and down, it will flow.

It's better to be so light that the injected water will float on it. Wet the coffee powder around it

Too much water will produce tension.

Will pull down the water that used to stay around the coffee powder.

The coffee powder does not have enough water to seep into the center of the coffee powder.

Just the right amount of water will form a bright surface of surface tension on the surface.

With the expansion of the air in the coffee powder and the air between the coffee powder.

The coffee powder layer will get higher and higher.

The coffee powder layer is also bright with water.

About 30 seconds or so...

The air in the coffee powder is due to a drop in temperature.

Begin to absorb the hot water that used to surround the coffee powder.

So there's no light on the surface...

As the surface moisture is absorbed... The surface is no longer shiny...

Cracks began to appear between the coffee powder

The top of the powder layer began to collapse.

After this time... The water around the coffee powder is also gradually absorbed dry.

And then... Getting drier and drier... The powder layer began to collapse more and more.

Until the water is sucked dry...

There are several factors that affect steaming.

The ratio of volume to weight of coffee beans.

Some coffee beans are big but light.

Some coffee beans are small but heavy.

The degree of baking will also be affected by the baking time.

To put it simply...

Is the amount of air contained in coffee beans.

Freshly baked coffee beans have more air capacity.

Coffee beans that have been exposed to moisture for a long time have less air.

The amount of air with deep baking degree is more.

The amount of air with a shallow degree of baking is less.

The amount of air that takes a long baking time is more.

The amount of air with short baking time is less.

After knowing the air content of coffee beans

Then there is the grinding scale.

Coffee beans are ground finely. The amount of air is less.

Coffee beans are ground thickly. The amount of air is more.

After the first two factors are determined...

And then there's the temperature of the hot water.

The higher the temperature...

The better the air expands.

But the higher the temperature, the greater the temperature difference between room temperature and room temperature.

The stronger the effect of thermal expansion and cold contraction.

The faster the coffee powder absorbs water... The water will be sucked dry and then the air will be inhaled. The faster it collapses.

The lower the temperature...

The lower the expansion effect of the air.

The coffee powder expands slowly and not too high.

Coffee powder also absorbs water very slowly, and it is not easy to inhale air again. It also collapses more slowly.

And then...

The size of the grinding scale is not as thick as possible. It's not as thin as possible.

It should be... Adjust according to the amount of air in the coffee bean itself.

If there is more air, you should grind it down.

If there is less air, you can grind it a little thicker.

Or to see if there is enough water to absorb the coffee powder when steaming.

If there's not enough water...

Can't seep into the coffee powder to completely dissolve the ingredients.

When the steaming second half of the coffee powder begins to dry

Will inhale the air again...

During the second water injection...

There will be a lot of big bubbles...

Increase the difficulty of extraction

Coffee powder floats on the surface.

Can't sink at the bottom to form a filter layer...

It is easy to form a deep V shape.

Coffee powder is finely ground.

Although the effect of steaming is better.

The air is easily driven out.

Enough water to absorb...

But also because after absorbing enough water,

The specific gravity becomes heavier. Easy to sink at the bottom

Forming a layer of silt...

Blocking the flow of hot water through the coffee powder layer

It's easy to flow sideways from the filter paper above the powder layer.

Judging from the above factors...

The effect of steaming...

Will affect the concentration of the whole cup of coffee.

So.

If you don't get bored in the first place... What should I do?

Is there no way to fix it when it is too difficult?

Please take a look at the next decomposition.