Why do you use a powder press for the powder hammer thing?

Why use a powder compactor

Baristas know that when using an espresso machine, the hot water brewed has a pressure of about 9 atmospheres (of course, this is not a fixed value, there are also 12 atmospheres or higher), the pressure is very high, and when the water penetrates the coffee cake, the water is inert.

What is inert is that water will penetrate through the weakest part of the coffee cake, not through the thickest part. Therefore, if you do not use a coffee press to compact and flatten the coffee (to make the coffee powder density in the powder bowl as uniform as possible), the essence of the coffee will not be extracted, or some parts will be over-extracted. That is to say, the main purpose is to flatten the coffee powder in the handle, tamp it, form a flat horizontal plane, better let the hot water extract through the coffee powder, and also to make the coffee powder withstand the huge pressure generated during the extraction of the coffee machine. The force of pressing powder should be determined according to the thickness of coffee powder grinding, and the reference is based on the flow rate of coffee during extraction (extraction time 25±5 seconds). If the flow rate is too fast, the powder pressing force is too light; if the flow rate is too slow, the powder pressing force is too heavy, which will directly affect the taste of the finished espresso and coffee.

In addition, everyone's application strength will be different, and there will be a big difference between boys and girls, so it is also necessary to adjust the corresponding strength according to the actual extraction effect. Everyone needs to pay attention to that powder pressing is only one of the links, and there are many factors affecting extraction, such as powder amount, powder thickness, powder cloth and powder pressing.

The following is a description of the various types of common powder press bottom (with a diameter of 58mm):

The classification of powder presses is mainly divided into 6 categories: 1.C-Flat; 2. Flat; 3. Ripple;4.C-Ripple; 5. Euro Curve; 6. American Curve.

The main difference is the shape of the base of the hammer.

Flat: The most common powder press, the bottom is flat bottom.

2. Euro Curve: The bottom of the powder hammer is arc-shaped, and the highest height difference at the edge of the powder hammer is 3.355MM.

3, C-Flat: belongs to the Euro Curve and Flat synthesis, it is not like Euro's bottom arc, but it is like Euro powder hammer is a height difference, the bottom is horizontal flat bottom, but the edge is arc-shaped, there is a height difference.

Ripple: It is difficult to control, the bottom of the powder hammer is wavy.

5. C-Ripple: On the basis of Ripple, improvements have been made. The bottom of the powder hammer is made into a flat bottom at the edge. There are multiple convex concentric circles in the center. The center of the pressed powder is wavy and the edge is horizontal.

6. AmericanCurve: The arc at the bottom relative to Euro Curve becomes smaller, and the height difference between the highest point of the arc and the edge of the powder hammer drops to 1.661MM.

Every barista wants to own or privately has his own Tamper(also called a powder hammer), because every cup of espresso coffee, coffee with a powder hammer to grind good coffee powder, thereby increasing the extraction quality of coffee (of course, there are individual practices are not pressed powder)

So what's the use of a powder hammer? Why is it so expensive to sell? Why is there a difference in size? Why is there a one-piece or a split? Why is the base different? How do we choose a powder hammer?

1, about the role of the powder hammer

There are several important functions of the powder hammer when making espresso coffee:

The first is to grind the coffee powder compact, so that hot water can fully penetrate and flow through the coffee cake;

The second is to keep the gap between coffee powder consistent, because coffee powder will begin to expand after absorbing water, which will easily make the extraction imbalance;

The third is to flatten the coffee powder in the handle to form a flat horizontal plane, so that the coffee powder can withstand the huge pressure generated by the coffee machine extraction without being washed and affecting the extraction taste.

2, about the powder hammer why there are size points

In fact, there are two sizes of powder hammers, the small size is about 49mm to 53mm (100px to 130px), and the large size is between 57.5mm and 58.5mm(143.75px to 1462.5px). The difference in specifications is mainly due to the problem of household Italian machines and commercial coffee machines. Generally, commercial coffee machines use large powder bowls, and each coffee machine company has its own set size, so there is a situation between 57.5mm and 58.5mm.

The manufacturer of the universal powder hammer will be 58mm, which is convenient for production and low cost. If you ask for a more precise size, the cost and technology will also increase, so the price will vary from tens of yuan to 300 yuan. The impact of the hammer will also increase with the company brand, hammer shape, material, weight, design or limited edition and other factors.

Well, through the above two points, it can be seen that the most important role of a powder press is to flatten and tamp the coffee powder. We can understand that the powder press has become a bridge between the barista and the coffee machine.

From left to right, RB black metal handle 58mm flat hammer bottom, RB black matte metal handle 58mm C-Ripple hammer bottom, domestic Brazilian rosewood wood handle 58.2mm flat hammer bottom, Pullman checkers handle matching La Marzocco powder bowl American Curve hammer bottom, German Concept-art metal adjustable pressure 58mm flat hammer bottom, La Marzocco original metal handle American Curve hammer bottom, Japanese aluminum alloy handle 53mm quantitative powder press.

If you have had the experience of customizing Pullman powder presses, Pullman official website will prompt you what machine to use, what powder bowl, what hammer bottom to adapt to, you can personally choose the handle that suits you. Obviously, the hammer base should fit the machine and the powder bowl, and the handle should fit the barista.

1. Choice of handle

It is best to fit your palm (as shown below)

2. Selection of hammer surface shape

What about the choice of hammer face? Please see below:

In this figure, the water distribution net and powder bowl are flat, so we naturally have to press the powder into a plane, so that the water from the plane of the water distribution net to extract the coffee powder will pass through the coffee powder with a vertical constant pressure. If we choose the powder press at the bottom of the arc, the middle of the coffee powder will be stressed too much, and the water flowing down the plane of the water distribution net will flow around because of inertia to avoid the difficult area in the middle.

The following pictures are Italy IMS 22g arc bottom traceless powder bowl, Italy LaMarzocco original powder press arc surface hammer bottom, Italy IMS adaptation LaMarzocco laser water separation net, Italy IMS adaptation LaMarzocco ultra-fine water separation net

You can see that the powder bowl, the hammer bottom of the powder press, and the water distribution net are all curved, and they can be completely matched! It can be imagined that water from the curved water distribution net flows through the pressed curved coffee powder and out of the curved powder bowl.

The above is the difference between arc bottom and flat bottom, that is to say, what kind of water distribution net and what kind of powder bowl are suitable for the machine, we will choose what kind of powder press hammer bottom.

3. Selection of size of powder press

The following is a 58mm flat bottom powder compactor hammer 53mm flat bottom hammer

As for the question of size, as mentioned above, it is determined according to the merchant, so why are there so many size to choose from, and then look at the picture in WBC World Champion Matt Perger's article:

Borrowing the pictures in WBC world champion Matt Perger's article, you can see that the more the powder press fits the powder bowl size, the less coffee powder remains on the wall of the powder bowl when pressing powder. Many baristas have the habit of knocking the handle after pressing powder in order to shake off the residual powder stuck to the wall of the powder bowl. Have you ever thought that this is caused by the improper powder press you chose? SYNESSO's original RB powder press is simply invincible, almost no residual powder. La Marzocco's original powder press is slightly inferior, but it is also very handy.

4, special shape powder press

Look at the picture below, three hammer bottoms correspond to three powder surfaces: thread, arc bottom, plane

Theoretically speaking, the powder surface pressed by the threaded powder press is wavy, which increases the surface area of the coffee powder, and the force when the 9bar water from the water separation net rushes to the coffee powder surface will be dispersed relatively, and the rate of water absorption on the coffee powder surface will also be relatively increased. In theory, it will increase the success rate of coffee extraction, similar to the coffee machine pre-soaking to improve the success rate of coffee extraction.

This is how the shape and size of the hammer base affect coffee extraction.

Summary: The right handle accurately carries the power of the barista, and transmits the coffee powder to the coffee machine through different hammer bottoms to understand the language read by the coffee machine, so that the powder press becomes a bridge between the barista and the coffee machine. Making a good cup of coffee starts with taking every detail seriously.