Every housewife is well aware that milk is a whimsical substance. It has the ability to foam when boiled, and "run away", flooding the stove, burning, creating an unpleasant odor and the risk of gas leakage if milk foam blows off the burner flame. At the same time, water, for example, does not possess such abilities, it simply boils and does not aspire to anywhere.
Why does milk “run away” but not water? What features of a healthy white drink make it so unstable? To answer such questions, it is necessary to consider the properties and composition of milk.
The boiling process and its features
Milk differs from water by the presence of considerable length in the composition of polymer fibers. In the process of heating milk, the water that forms its bulk is evaporated, the process occurs primarily in the surface, near-surface layers. In this case, polymer molecules exhibit the ability to form the thinnest film — they stick together and join together. The film could simply be on the surface, without disturbing anyone, but at the bottom of the pan during the boiling process bubbles begin to appear, consisting of gas that was dissolved in the liquid.
Bubbles increase, with growth their own walls strengthen - inside the process of evaporation also goes on, polymer films grow around them. At a certain moment of boiling, the bubbles begin to intensify upward.But their own shells are sealed with polymers, and when they rise, they also stick into the polymer surface of the film formed in the upper layers.
With the accumulation of bubbles, a foam forms, which tends upward and lifts the formed film. They themselves do not burst due to increased strength, and every minute they become more and more. At some point, they rush upstairs en masse, and milk "runs away". If you miss this moment, a catastrophe will begin on the stove: a large amount of liquid will be on the stove, it can burn, emitting an unpleasant odor. At a minimum, a long cleaning of a negligent housewife will be provided.
What to do so that milk does not run away?
This behavior of milk is not happy, but there are several ways to tame the rebellious elements and boil a useful product without incident. First of all, it makes sense to start stirring the milk as soon as it approaches the boiling point in temperature. Many housewives dispense with this simple method, which forces them to be constantly at the stove, but gives a 100% result. After stirring, the film does not form, and the bubbles come out freely.
There is another option, more tricky. You can put an inverted saucer at the bottom of the pan with milk, and then the milk will also not froth and run away. This solution works as follows: under the saucer, the bubbles accumulate and rise up only becoming large enough. And large bubbles easily tear the film and leave the pan freely.In this case, you will not have to constantly stand by the stove; the process will occur without human intervention.
Interesting fact: special metal plates of a special shape are produced, which are placed on the bottom of the pan. They work exactly like saucers, collecting bubbles from special grooves and releasing them through the spout. The product is called “milk watchman”.
Another way to keep milk in a container is to boil it in a water bath. Choosing this solution, you can completely eliminate boiling with the release of foam, but you will have to spend more time.
Why does water boil, not run away?
Water can boil without the formation of stable bubbles - it will boil away only in case of overcrowding of the container or excessively strong temperature. Bubbles when boiling water also form at the bottom, and then freely rise, leave the water column and release their contents into the air. Without encountering obstacles, the water boils without the formation of dense foam, which can overflow onto the stove.
Thus, milk creates a foam that “escapes” from the pan, due to the presence in the composition of polymeric substances that form a film on the surface and stabilize the walls of the bubbles. Water does not have polymer components, proteins are not included in it, and therefore no films or other elements that would impede the boiling process and create additional difficulties are not formed in it.
