How do I play the coffee foam? What is the standard of dense milk foam?

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The first point is that "the surface should be reflective". This statement is very objective and direct, at least it can be used as a standard to be seen by the naked eye.

The second point is that there is no coarse foam on the surface. This requires a lot of foam control ability, of course, this is also the premise of reflection. So what is a coarse bubble? If we have to give it a definition, I think those larger than the diameter 1mm will be called coarse bubbles. The more delicate the milk foam is, the less air is contained in a single milk bubble, the higher the density and the less buoyancy is; the rougher the milk foam is, the less air is contained in the single milk bubble, the lower the density and the greater the buoyancy. If the milk foam is rougher, the foam will float quickly on the surface of the milk and the degree of fusion will be lower; if the foam is more delicate, the speed of the foam floating on the surface of the milk will be slow and the degree of fusion will be higher.

The third point is: in the case of the same amount of milk (all added to the position around the bottom of the cylinder mouth), no matter 60% full or 70%, 80%, 90% or full, the temperature should be the same, and the number of milk bubbles cannot be adjusted by the temperature.

The fourth point is to make two cups of cappuccino, using the WBC standard cup. After the foam is poured into the cup, there is no drop left in the jar. If this standard is a little bit more flamboyant, it will become: you can only beat as many milk bubbles as you want (except for micro-bubbles such as macchiato), which is very difficult to practice and takes a long time.

The above four standards have been achieved, at least it can be regarded as a good bottle of milk foam in terms of vision, feel and technology. I also mentioned a sense of hearing, which depends on the milk. When you hit the milk foam, you must listen to the "squeak" sound of air intake, so as to ensure the persistence of the milk foam in the cup.

How on earth do you play the milk foam?

First, pour half a cup of milk into the steel cup and put the steam pipe into a position about 1 cm deep from the surface of the milk. while playing the foam, observe the state of the foam and adjust the position of the steam pipe to the position where there is no blister. hit until foaming first, the foam will slowly become dense, about 50 degrees Celsius to turn down the steam, 65 degrees Celsius should be turned off.

Second, the milk foam is the best state at this time. If the temperature is too high or played for too long, the milk foam may be defoamed, thickened or reduced to milk. The temperature of the steam is so high that it is wrapped in a rag to avoid scalding.

Third, after beating, the upper foam is usually thicker, and the upper thick foam can be removed. The surface of the dense foam below will have a mirror smooth effect, and it will flow out smoothly instead of caking when it is poured out. When shaking the cup, the foam will have a slippery feeling and taste elastic, so it is the perfect foam!