Solution to the problem of decomposition of latte Milk foam

I don't know if you have ever tried to open the lid to observe the foam when you order a take-out latte. At first, the editor will get used to opening the lid to see the flowers, but later to observe the fineness and stability of the milk foam.

Sometimes, the milk foam in the cup is not bulging, but concave; sometimes, the milk foam looks very hard, no matter how shake, the milk foam still does not move. Sometimes, when you just open the lid, the foam is still extremely delicate, but within 2 minutes you can see the foam decomposing with the naked eye. If you are in a quiet environment, you can still hear the sound of "xi~xi~" like defoaming detergent foam. Of course, the editor is not so unlucky, in most cases, the latte is still delicate and slippery, and the delicate layer of foam and flowers are still intact at the bottom of the cup after drinking.

In view of the various phenomena of these latte bubbles, Qianjie felt that the reasons for these situations were analyzed one by one. First of all, the foam is sunken, that is, the bubble collapses. The main reason for this is that the milk foam is too thick and the oil is too thin. The previous article in the mocha pot on the front street has said that coffee can fuse and pull out a pattern without oil. But careful friends may find that there is no oil fusion of milk foam, the color is light, coffee oil is a stabilizer to maintain milk bubbles. Although it can be delicate at first, bubbles can be easily broken down without grease. When the bubble cannot hold the weight, it will burst. Then when the milk foam layer is thicker, it will collapse, that is, the surface of the cup of coffee we see is concave.

Then there is the problem of hard foam and serious layering. Basically, lattes can't escape this outcome in the end, but a well-integrated latte can slow down layering. Too much foam can also lead to serious layering of lattes. You can try it. When you just make a latte, take a sip immediately, and the milk foam on the surface will flow with it. And placed for about 5 minutes to drink the first sip, will only open a small hole in the surface of the foam, drink is the latte under the foam. If the milk foam is too thick or improper fusion, it only takes 2 minutes to achieve this effect.

The surface of the coffee disintegrated. It is mainly caused by the instability (roughness) of coffee oil. Oil has the effect of stabilizing milk bubbles, and when the oil is unstable, it is easy to disintegrate the originally stable milk foam layer. Causing the latte surface to feel awkward or dense bubbles.

There are two main possibilities for oil instability. The first is that coffee beans are too fresh, that is, the difference between baking time and use time is less than 7 days. At this time, the carbon dioxide in coffee beans is still relatively rich, which will make the oil unstable during extraction. Easy to decompose into big bubbles. The second is caused by improper extraction. The other is that there is no problem with coffee fat and milk foam, and after making a latte, the surface is also very smooth and delicate. But after a while, there were big bubbles in the circle near the wall of the coffee cup, but it was delicate in the middle. This is mainly caused by water stains in coffee cups. If there is the influence of water, then the milk foam near the edge of the cup will decompose unsteadily. While the center is stable.