How to foam on the coffee machine-Delong coffee machine steps

How to foam on the coffee machine-Delong coffee machine steps

[1] the direct reason is that some bubbles are brought into the liquid, and in milk bubbles, these bubbles are made more stable by a layer of inclusions around them (by increasing surface tension). In most edible milk foams, protein acts as this inclusion, because part of the protein molecule is hydrophobic and repelled by water, so this part of the protein molecule is also more likely to come into contact with substances other than water. In general, protein molecules are rolled up in aqueous solution, and their hydrophobic parts are inside the molecules; for them to form milk bubbles require some operations, such as heating (or, in the case of egg whites, strong beating). The bubble acts as a moderator of the hydrophobic part of the protein molecule, while the protein molecules are arranged linearly at the gas-water intersection-that is, the surfactant.

[2] Why did the milk foam burst? If it is a milk bubble formed by surfactant in water, then the main cause of rupture is water loss. The bubbles pull each other by gravitation, and the surfactant is slowly consumed. As a result, the foam becomes fragile and inelastic, so that it finally breaks. However, this does not answer why mistakes may occur when using steam to beat milk foam, and in this case, the main cause of foam rupture is fat. Fat and water are immiscible because water has polarity and fat has no polarity.

[3] part of the protein is also rejected by water because of its lack of polarity. If fat is also present in the milk bubble system, then there is another option for the non-polar part of the protein-it can wrap small "bubbles" of fat. That's why fat makes the foam unstable, and that's why your steam milking is over. (by the same token, if you want to get rid of egg whites

The first step: first do fast low hit, hit until there is obvious resistance and continuous feeling; then do medium hit, also hit obvious resistance and continuous feeling; finally do high hit, hit as a whole have resistance and continuous feeling. Tip: pay attention to the height of the twitch.

Step 2: repeat the first step. In this way, the process of manual milking is completed. If you want your foam not to be too thick, to have a certain sense of flow, just take the first step. Pulling out the piston vertically after foam is helpful to drive out a lot of coarse bubbles. (since the picture has not been downloaded, we do not know the specific samples of the author's low, medium and high hits.)

Production of hand-made hot milk foam

Heat the milk (milk that can be foamed and held, recommended Nestle) to a temperature that is hot (60 to 70 degrees) but can be held. What kind of heating method is used is not important, the key is to reach this temperature (why this temperature should be reached will be discussed later). The heating method used in the store I have instructed is the microwave oven. at first, it is slowly trying to find out how long it takes to heat the milk to the target temperature with a big fire, and then just put the milk in and heat it at the time after the test. it's very convenient and very fast.