In many countries in the world (especially in Asia), drinking hot drinks is a daily habit. When you discuss drinking hot milk with your friends, your friends may tell you a frightening thing: heating milk may cause nutrition loss and even produce harmful substances.
but is it really the case?
” Protein denaturation” will not reduce the nutritional value of milk
We ingest protein not for the sake of the protein itself, but to obtain the amino acids that make up the protein.
From protein to amino acid, protein is not only ” denatured”, but also cut into small peptides and amino acids by digestive enzymes.
The ” denaturation” usually refers to that the protein loses its natural spatial configuration and stretches out the molecules, which facilitates the full contact between digestive enzymes and protein and is conducive to digestion.
So, if someone tells you that heating milk will cause protein denaturation, you don’t have to worry about it.
Boiling milk will not produce harmful substances
You may hear your friend tell you that heating milk will cause protein to burn.
The so-called ” protein scorching” is actually Maillard reaction between amino acids in protein and lactose. Fructosyl amino acid is one of the products of Maillard reaction.
Fructosyl amino acids are indeed no longer amino acids. Theoretically, this reaction does ” reduce” the nutritional value. However, the suitable conditions for this reaction to occur efficiently are ” high temperature” and ” low water content”. If Maillard reaction takes place, as long as there are few products, the color will become darker and different flavors will appear.
The ” warm milk” on the market was heated to over 135 ℃ in the production process, and the degree of Maillard reaction was still very low, just ” sensitive people can experience different flavors”. For milk powder with more extreme heating conditions, the milk is concentrated and then spray dried-the water content is very low, the temperature of hot air is very high, and the degree of Maillard reaction is not high.
In everyone’s daily experience, by heating the milk to boiling, you will not see the color darkening and ” burnt flavor” condition. This means that the degree of Maillard reaction is negligible. To say that this product ” affects human health” is purely to frighten the public-just like dropping a packet of salt into a reservoir and saying that it may cause hypertension in residents drinking water.
In short, the so-called ” milk boils to produce harmful substances” is totally unfounded.
Heating milk is not for sterilization
No matter whether it is pasteurized milk or warm milk, it does not require additional heating and sterilization by consumers.
Of course, this only means that ” heating the milk to boiling” will not be harmful and the loss of nutrition will be minimal, which does not mean that boiling the milk is recommended.
Heating milk has two purposes: one is sterilization, and the other is to reach ” appropriate temperature”.