The principle of coffee cream foam how to calculate dense milk foam layering

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First of all, we need to know what kind of milk foam is good when pulling flowers in coffee? I think there are three criteria for good bubbles:

Second, there are no air bubbles on the surface.

Third: glossy and mobile

I will divide the coffee lace into two stages to make milk foam:

The first stage is to get rid of it: the so-called dismissal is to put in steam to make the volume of milk foamy and expand.

The second stage is to make the foamed milk make use of the swirl of the milk in the cup, and decompose the larger foam into fine foam, and let the milk molecules bond with each other, so that the foam tissue becomes more delicate and dense.

How to get rid of milk: this process is relatively simple, let the liquid surface of the milk cover the steam head shallowly, turn on the steam switch, you will hear the sound of puffing in the ear, and you will see irregular bubbles on the surface. this is the normal foaming stage.

About the thickness of the foam: people often ask how thick the foam should be, or how many minutes the cup is full. The thickness of the foam varies with different machines at the same foaming time, including the same foaming time of milk. About thin and thick here I told the students, milk in the prostate, such as 200ml sent into 210ml, then this 10ml is the amount of foam, then this is relatively thin, for example, milk is sent before 200ml into 400ml, then the amount of foam is 200ml, then this is relatively thick, so thickness depends on the amount of foaming to you (can also be understood as the amount of air), can be sent according to the need.

Beating stage: the beating stage is the most important link in the milk foaming process, so two points should be considered: (note: during the beating stage, the milk tank should be raised to cover the steam head.) the first angle: it refers to the angle formed between the steam rod and the milk surface. We need to know that the steam bars of most commercial semi-automatic coffee machines are four-hole, that is, spraying steam in four directions. Then if the steam rod is perpendicular to the liquid level, it must not rotate, so the angle between the steam rod and the liquid level should be between 30 °and 60 °.

The second point position: refers to the position of the steam head on the liquid level, we can think of the liquid level of milk as a clock, in front of us at 12:00, no matter what angle the steam rod touches the liquid surface, the position where it is easiest to rotate is neither the midpoint nor the 12:00 and 6 o'clock positions, the easiest points to rotate are 3 o'clock and 9 o'clock (unbelieving friends can test it) So the best position is 3: 00 on the right or 9: 00 on the left.

The two stages are connected together is the whole process of milk foaming, foaming is carried out first, and when the foaming amount reaches the amount you need, the milk tank is gently lifted up for the beating stage, and the steam is turned off when the temperature reaches the specified temperature. Clean the steam stick and discharge steam immediately after foam, and shake the milk tank to avoid milk delamination.

The choice of coffee lace milk:

Temperature: the best temperature before milk is about 4 °, that is, frozen milk, cold milk will give us a longer time to kill and beat, so it is relatively easy to make dense and delicate milk foams. and ice milk will have more fat and protein content than normal temperature milk, milk in the process of storage, each rise in milk fat and protein will be a small amount of decomposition.

Fat content: the best milk to get rid of foam we all know is whole milk, whole milk is defined as: every 100 milliliters of milk, fat and protein content is greater than or equal to 3G. The higher the fat and protein content, the finer and more stable the foam is, and it is not easy to delaminate.