Why do you press coffee powder when it is made? How much is the appropriate filling pressure to make coffee?

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One of the steps in coffee making is to fill the loose coffee powder with a filler, which can be compacted to operate the next coffee extraction. Many friends who do not understand this step will ask, why does coffee powder have to be filled and pressed before it can be buckled and extracted? So what's wrong with the extraction if the coffee powder is not filled and pressed? I'm afraid this is a question that most friends who don't know about coffee making will ask. So let's find out why coffee powder needs to be filled, how to fill it, and how much is appropriate?

Light pressure VS heavy pressure

With the upgrading of technical awareness, it is believed that there are few baristas who will struggle with heavy pressure or light pressure.

First of all, we have to make it clear that the purpose of pressing powder is to remove air from the pressed powder and compact the structure of the powder layer, so that it can be extracted evenly during extraction and avoid over-extraction.

So for me, the filling force of 15kg is enough to remove the air from the powder layer and make the powder layer dense.

In my opinion, more than 15kg filling force is futile, because the water under the strong pressure of 9bar, the kg force built on the powder layer far exceeds your weight, even if you jump up and down pressure, it is meaningless.

In addition, you also need to take into account the opponent's wrist injury, and the consistency of each force, if the set force is too large or size, the consistency is easy to deviate.

two

One-time filling VS multiple packing

On this issue, I think that as long as it is man-made technical work, there will eventually be mistakes, and the difference between experts and beginners only lies in the probability of mistakes.

Such being the case, why should the process of leveling and filling be carried out many times when it can be achieved at one time?

Of course, some baristas believe that the residual powder on the surface of pressed powder after one filling will affect the extraction results, so it needs to be filled into pressed powder again. Friends who have this idea may not fully understand the extraction method of coffee machine cooking head.

However, I would like to make an exception here, unless you use the 58mm whole or small pink hammer and intend to do the "four-way packing" technique, there is no reason for me to do multiple packing.

PS: "four-way packing" means that when there is no large diameter powder hammer, the edge of the powder bowl is deliberately pressed up, down, left, right, and four sides once, in order to prevent the channel effect caused by the small diameter of the powder hammer.

three

Upright lift VS rotary powder hammer lift

As I mentioned earlier, the residual powder on the edge of the powder bowl will be extracted as long as it is still in the powder bowl.

Therefore, the purpose of "rotating powder hammer again" is only to bring down the residual powder around the powder bowl, which is of no practical help to the extraction.

Of course, there are also baristas who believe that the action of rotating the powder hammer will offset the thick and fine powder on the surface of pressed powder, resulting in a difference in extraction.

Then you can do some experiments, such as sprinkling some fine sugar on the filled pressed powder, and then rotating to see if the sugar deviates.

There is so much knowledge about the filling of coffee. Really, if you don't know it, you may be laughed at. The fundamental meaning of coffee filling is to make a good cup of coffee in order to be worthy of the customer's choice. Making a cup of coffee requires such complicated steps, it is all in order to give you a cup of coffee that can satisfy you. What a painstaking effort!

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