Milk is an incredibly valuable product that people have included in their diet since ancient times. It is drunk as an independent drink, and also included in the composition of various dishes.
Cow milk is the most popular among Europeans. What exactly is this drink useful and what elements contains, let's understand together.
Calorie and nutritional value
The energy value of 100 g (100 ml = 103 g) of the product is 60 kcal or 250 kJ. 1 l of milk in calories is close to 370 g of beef or 700 g of potatoes.
On average, 100 g of drink contain:
- proteins - 3.2 g;
- fat - 3.25 g;
- carbohydrates - 5.2 g;
- water - 88 g;
- dry matter - 12.5%.
Did you know? In ancient Russia, in order to stop the process of souring, a frog was thrown into a jug with milk.
What is contained in cow's milk
The chemical composition and caloric content of milk are not constant.
The fact is that the number of minerals, vitamins and the percentage of fat content depend on the season, the conditions of the cow, the menu and the state of animal health, age and other factors that affect milk production and milk yield.
Even for one annual lactation, the duration of which is about 300 days, the composition, appearance and taste of the drink changes three times.
Like most foods, milk contains proteins, fats, carbohydrates, vitamins and minerals. We offer a closer look at the average chemical composition of the drink.
Find out what are the processing methods and types of cow's milk.
Squirrels
It is believed that proteins are the most valuable substances in the composition of milk. In particular, the beverage contains complete proteins, including 20 amino acids, including 8 essential ones. 
Casein is a complex protein whose benefit and harm to a person causes a lot of discussion. One of the latest scientific studies suggests that casein can be assimilated by the human body only until it reaches the age of 9-10 years. Then the rennin enzyme, which is responsible for its cleavage, is no longer produced.
Therefore, in order to break down this protein, the stomach produces more hydrochloric acid. Casein accounts for about 81% of all proteins in milk.
Find out why there is blood in the milk of a cow.The beverage also contains whey proteins - albumin (0.4%) and globulin (0.15%). These are simple squirrels in which advantage nobody doubts. They contain essential amino acids and sulfur. The human body absorbs them by 96-98%.
Another protein that is part of milk and is important for humans is fat globules. The compounds that it includes form a lecithin-protein complex.
Protein in milk: video
Milk fat
Milk fat has the form of balls with a diameter of 0.5-10 microns, placed in a shell with a complex structure and composition. Fat contains acids - oleic, palmitic, butyric, caproic, capric, neutral fats, as well as substances related to fat-like - phospholipids, lecithin, kefalin, cholesterol, ergosterol.
The human body absorbs milk fat by 95%.
Important! Despite the undeniable biological and nutritional value, there is an assumption that milk fat, due to its saturated fatty acid content, can increase cholesterol levels in the blood and thus lead to the risk of atherosclerosis and cardiovascular diseases.
Milk sugar (lactose)
Milk sugar is almost the only carbohydrate that gets to a newborn mammal through food. The undoubted advantage of lactose is that it is a source of energy and an active participant in calcium metabolism.
Lactose breaks down the enzyme lactase. Milk sugar is slowly absorbed by the stomach and intestines. And getting into the colon, provokes the growth of beneficial bacteria that produce lactic acid and inhibit the development of pathogenic microflora.
Milk sugar is absorbed by the human body by 99%.
Video: the useful lactose in milk
Vitamins
Of the vitamins in milk, cows are present:
- vitamin A (retinol) - 28 mg;
- Vitamin B1 (thiamine) - 0.04 mg;
- vitamin B2 (riboflavin) - 0.18 mg;
- Vitamin B12 (Cobalamin) - 0.44 mcg
- Vitamin D - 2 IU.
Find out what milk coolers do and what they are like.Thiamine takes part in metabolic processes, stimulates brain activity, blood formation.
Riboflavin is necessary for the normal functioning of almost all systems. He participates in redox reactions, the conversion of amino acids, the synthesis of various vitamins.
The main function of cobalamin is to participate in the formation of red blood cells and nerve fibers, as well as in the process of metabolism.
The benefits of vitamin D are invaluable. Without it, the metabolism, the processes of assimilation of phosphorus and calcium, the activity of the nervous system cannot normally proceed.
Important! Despite the enormous benefits of milk for humans, it should not be consumed by people with individual lactose intolerance, diseases of the gastrointestinal tract, liver, pancreas.
Minerals
Total milk contains about 50 minerals.
The most significant of them are:
- calcium - 100-140 mg;
- magnesium - 10 mg;
- potassium - 135-170 mg;
- phosphorus - 74-130 mg;
- sodium, 30–77 mg;
- chlorine - 90-120 mg.
Calcium in the drink is well digested by the human digestive tract and is in optimal balance with phosphorus. Its level depends on nutrition, breed, lactation phase, time of year. In the summer, it is much less than in the cold season.
The phosphorus content is almost always stable and little dependent on external factors. So, only in the spring period its level can be somewhat reduced. But the breed of the animal, the quality of its food and lactation significantly affect its content.
Find out what helps and how to prepare milk with cinnamon, milk with garlic, milk with propolis.Magnesium in cow's milk is not much, but this element is very important for the formation of the immunity of offspring, its growth and development.
The level of potassium and sodium varies depending on the physiology of the animal, and also varies slightly at different times of the year.
In a small amount in the drink contains trace elements: iron, copper, zinc, manganese, cobalt, iodine, silicon, selenium, etc.
The chemical composition of the milk of other animals
Cow's milk is the most popular species among other mammals. Goats' milk is much less commonly consumed. Some nations use camel, sheep and the one given by lamas. 
Depending on the type of animal nutritional content and composition of milk differ significantly. Although each of them necessarily contain fats, protein, carbohydrates, vitamins and minerals. Below you will find the approximate composition of the fluid that forms in the mammary glands of female mammals.
| Kind of milk | Proteins,% | Fat% | Carbohydrates (lactose),% | Water% | Dry matter,% | Minerals mg |
| Goat | 3-3,3 | 3,6-6 | 4,4-4,9 | 86,3-88,9 | 13,7 | calcium - 143; phosphorus - 89; potassium - 145; sodium - 47 |
| Mare | 2,1-2,2 | 0,8-1,9 | 5,8-6,7 | 89,7-89,9 | 10,1 | calcium - 89; phosphorus - 54; potassium - 64 |
| Camel | 3,5-4 | 3-4,5 | 4,9-5,7 | 86,4-86,5 | 13,6 | |
| Deer | 10-10,9 | 17,1-22,5 | 2,5-3,3 | 63.3-67,7 | 34,4-36,7 | |
| Sheep | 5,9 | 6,7 | 4,8 | 18,4 | calcium - 178; phosphorus - 158; potassium - 198; sodium - 26 |
Did you know? The Chinese, Africans, American Indians and residents of Southeast Asia lack the gene responsible for lactose absorption. Therefore, milk is consumed only by children under 5 years of age. Adults do not drink it because of intolerance.Thus, milk is a popular drink, the production of which is a large industrial branch. This drink is of great value for humans, because it contains a number of elements necessary for it, in particular proteins, milk fat, milk sugar, vitamins, macro- and microelements. However, you can not drink it all. Some people have an individual intolerance to this drink.
