Milk and dairy products nutritional value. Nutritional value of milk and dairy products

PART I GENERAL DAIRY TECHNOLOGY

Chapter 1. Milk as a raw material for the dairy industry

Food and biological value milk

Milk (lactate) is a biological product of the secretory activity of the mammalian mammary gland. It fully provides all the necessary nutrients for the normal development of the newborn. Possessing immunological and bactericidal properties (the ability to destroy and suppress the development of extraneous microflora), milk protects it from diseases, participates in the formation of its enzyme and immune systems.

The composition of milk in optimal harmonic combinations includes: proteins, lipids, carbohydrates, minerals, water, organic acids, gases, pigments, vitamins, enzymes, hormones, immune bodies and others essential components for normal feeding and metabolism of the cub. Milk, containing in a balanced qualitative and quantitative composition more than 250 vital substances with easy and almost complete digestibility (96-98%), has no equal product in nature in terms of nutritional and biological value.

Since ancient times, milk has been used not only for nutrition, but also in medicinal and preventive purposes, therefore it was called the "source of health", "food of the gods".

According to the definition of the great Russian physiologist I.P. Pavlov, "milk is an amazing food prepared by nature itself." He pointed out that milk has the ability to independently, without the participation of the cerebral cortex and in the absence of appetite, excite the digestive tract, cause the separation of digestive juices and be absorbed, “without which the digestion of other food cannot occur”; this is especially healing properties milk for sick and weakened organisms; in addition, milk proteins are easier and more fully digested than the proteins of other products, and contribute to the absorption of the latter.

All components of milk are complete and play an important role in the physiology of human nutrition.

Milk proteins are the most biologically valuable component. The amino acids formed during the breakdown of proteins are the material for building body cells, enzymes, hormones, antibodies during manifestations of immunity, etc. Of all animal proteins, milk proteins are the most complete. Casein, albumin and globulin contain all essential amino acids (lysine, tryptophan, methionine, phenylalanine, leucine, isoleucine, threonine, valine). A dietary deficiency of at least one essential amino acid causes a metabolic disorder in the human body. Whey proteins are more valuable than casein because they contain more lysine, tryptophan and other essential amino acids. Milk proteins have lipotropic properties, regulating fat metabolism, increase the balance of food and the absorption of other proteins. With amphoteric properties, milk protein protects the body from toxic substances. When the body is poisoned with heavy metals, casein reacts with them, forming insoluble salts that are excreted from the body.

It is important that the proteins in milk are in a dissolved state, therefore they are easily attacked and digested by proteolytic enzymes. digestive tract. The digestibility of milk proteins is 96-98%.

The sulfur-containing amino acid methionine is a source of the formation of choline and phosphatides, which play an important role in metabolism, preventing fatty degeneration of the liver, atrophy of the endocrine glands, changes in the transmission of nerve excitations, etc. Milk protein amino acids arginine and threonine normalize the processes of growth and development and are therefore especially important for the child's body.

The daily requirement of an adult in amino acids (28.4 g of milk proteins or 14.5 g of whey proteins) is fully provided by consuming 0.5 liters of milk.

Milk proteins have a water-binding, emulsifying, foaming ability, which allows them to be used in the production of combined biologically valuable products.

milk fat compared to other natural fats, it has the most complex chemical composition (more than 157 fatty acids are involved in the formation of its glycerides). Its qualitative and quantitative glyceride composition is optimally balanced. Of the natural fats, it has the most valuable nutritional properties, is a source of energy for biochemical processes in the body.

Milk fat is highly digestible. This is due to the fact that it is found in milk in the form of easily digestible microscopic fat globules in liquid state. The melting point of milk fat is 27-34 °C. The biological value of milk fat is due to the content of fat-soluble vitamins (A, E, D) and essential polyunsaturated fatty acids (linoleic, linolenic, arachidonic). However, milk fat contains an insufficient amount of polyunsaturated fatty acids, covering the need human body by one third. Therefore, the addition of vegetable oil rich in linoleic and linolenic fatty acids is recommended. The lack of polyunsaturated fatty acids in the body contributes to the development of atherosclerosis, vascular thrombosis, dry skin, eczema and other diseases. The lipoids associated with milk fat (phospholipids, lecithin, cerobrosides, stearins, waxes) play an important role in cellular metabolism, the intensity of fat absorption, and in the formation of adrenal hormones.

The pleasant taste of milk fat ennobles the taste of dairy products, determines the homogeneity and plasticity of their structure and consistency.

Milk sugar (lactose) is a source of energy for biological processes in the body, promotes the absorption of calcium, phosphorus, magnesium, barium. Possessing less solubility than sucrose, it causes less irritation of the digestive tract, and due to delayed hydrolysis, it reaches the large intestine, where it is used by lactic acid microflora, which creates a favorable acidic environment. Having 5 times less sweet taste than sucrose, lactose does not reduce appetite.

Milk minerals play a significant role in the plastic processes of the formation of new tissue cells, the synthesis of enzymes, vitamins, hormones, as well as in the mineral metabolism of the body. Milk contains a lot of calcium and phosphorus salts, which are in an optimally balanced ratio and easily digestible form. These elements are necessary for the body to form bone tissue, blood formation, brain activity, etc. Approximately 80% of a person's daily need for easily digestible calcium is met by dairy products. Calcium is needed to regulate blood pressure, reduce the risk of certain types of cancer; iodine is involved in the synthesis of the thyroid hormone - thyroxine; iron is part of hemoglobin and some enzymes; cobalt is part of vitamin B12; copper catalyzes redox processes in the body; sodium and potassium chlorides, phosphates are involved in the construction of blood and plasma elements; sulfur - in the synthesis of most proteins, a number of vitamins, hormones and other biologically active substances.

The biological value of milk is complemented by the presence of almost the entire complex of vitamins known and necessary for the human body, the content of which varies depending on the period of the year, on animal feeding rations; it, as a rule, rises in the summer when livestock is kept on green pastures.

One liter of milk fully satisfies the daily requirement of an adult for animal fat, calcium, phosphorus; 53% in animal protein; 35% - in biologically active essential fatty acids and vitamins A, C, thiamine; 12.6% in phospholipids and 26% in energy. The energy value of milk is 2720 kJ/kg.

The presence of all components in an optimal combination and easily digestible form makes milk an extremely valuable, indispensable product for dietary and medical nutrition, especially in gastrointestinal diseases (colitis, cholecystitis, acute gastritis), heart disease and blood vessels, liver, kidney, diabetes, obesity. Milk should be consumed daily to maintain tone and increase life expectancy.

Milk is of exceptional importance in the nutrition of children, especially in the first period of their life. The shell protein of fat globules contains a significant amount of phospholipids, arginine and threonine - amino acids that normalize the processes of growth and development of the body. Milk is the main source of easily digestible phosphorus and calcium for building bone tissues of a growing organism.

The biological value of milk is complemented by the fact that it contributes to the creation acid environment in the intestinal tract and suppression of the development of putrefactive microflora.

Milk plays an equally important role as a dietary and medicinal product for the elderly, this was pointed out by Avicenna, who lived over 1000 years ago. Milk and dairy products must account for at least 20% daily diet old people. For an aging body, the nature of nutrition is a very important factor in health and life extension. This is due to the fact that in people over 60 years of age, the intensity of metabolic processes and the digestibility of food are reduced, there is a lack of digestive enzymes, and the secretory and motor functions of the gastrointestinal tract are weakened.

They have a depletion of the skeleton with mineral salts, a change in vitamin metabolism, and fluctuations in the composition of the blood. The body's resistance to the effects of adverse weather conditions and the body's resistance to diseases decrease over the years. A balanced and rational diet can largely counteract these processes.

With age, not only the intensity of metabolic processes in the body decreases, but also the need for nutrients ah, there is selectivity in their choice. The need for meat is sharply reduced and the need for vegetable and dairy products increases.

Milk and dairy products are essential in the diet of the elderly. In this case, it is advisable to give preference to low-fat or low-fat dairy products. The desired ratio of animal and vegetable proteins and fats is 1:1.

Currently, dairy and vegetable-dairy products are being created for the therapeutic and prophylactic nutrition of the elderly.

A very important role in the nutrition of the elderly is given to dietary fermented milk products, which are most easily and quickly absorbed by the body, require less digestive juices, and heal the gastrointestinal tract. Dietary fermented milk products with therapeutic and prophylactic properties, fortified, with vegetable biologically valuable fillers are being created.

To fully meet the needs of the population of the Russian Federation in dairy products, it is necessary to process more than 50 million tons of milk per year with an increase in the capacity for the production of dietary fermented milk products, cottage cheese, cheese and canned milk.

Milk and dairy products

Introduction

Milk -- the only product nutrition in the first months of a person's life. For old, weakened and sick people, milk is an indispensable food.

“Milk,” wrote academician I.P. Pavlov, “is an amazing food prepared by nature itself.” IP Pavlov believed that milk is in an exceptional position among other products of our diet, is the easiest food.

Right organized meals the patient not only satisfies the needs of the body, but also actively influences the course of the disease. Taking this into account, a system of therapeutic nutrition has been developed, the principles of which are widely used in medical practice. Of great importance is the amount of food consumed, as well as its temperature. The latter should not exceed 60°C, and be below 15°C, with the exception of special cold dishes, such as cold milk or sour cream for stomach bleeding. The frequency of food intake is not less than 4 times, and in some diseases, in particular, with peptic ulcer of the stomach and duodenum, up to 5-6 times a day.

Milk. Nutritional and biological value of milk and dairy products

It is well known that milk is the most important product baby food. Milk is an extremely valuable product in the diet of adults. Very often, milk and dairy products are underestimated in our diet and they prefer meat, fish, eggs.

The main qualities of milk are its easy digestibility, the content of high-value proteins and fat in it in a fairly significant amount, the presence of various mineral salts, as well as vitamins.

The nutritional and biological value of milk lies in the optimal balance of its components, easy digestibility (by 95-98%) and high use of all the plastic and energy substances necessary for the body. Milk contains all the nutritional substances necessary for the body, therefore milk and dairy products are indispensable in the nutrition of patients, children and the elderly. It contains high-grade proteins, fats, vitamins, mineral salts. In total, about 100 biologically important substances have been found in milk. Inclusion of milk and dairy products in diet improves the balance of the amino acid composition of the proteins of the entire diet and significantly increases the supply of calcium to the body.

The chemical composition of cow's milk is as follows: proteins 3.5%, fats 3.4% (at least 3.2%), carbohydrates in the form milk sugar(lactose) - 4.6%, mineral salts 0.75%, water 87.8%.

The chemical composition of milk varies depending on the breed of animals, the season, the nature of the feed, the age of the animals, the lactation period, and the technology of milk processing.

Milk proteins are represented by casein, albumin (lactoalbumin) and globulin (lactoglobulin). The composition of milk proteins includes amino acids necessary for the body (tryptophan, phenylalanine, methionine, valine, lysine, threonine, histidine, isoleucine and leucine).

Milk proteins are readily available for digestive enzymes, and casein has a regulatory effect on increasing the digestibility of other nutrients. Casein, when souring milk, splits off calcium and curdles. Albumin - the most valuable milk protein, when boiled, coagulates, forming foam, and partially precipitates.

In human nutrition, cow, goat, sheep, mare, donkey, deer, camel, buffalo milk is used. Buffalo and sheep milk has especially high nutritional and energy properties. The most nutritious is reindeer milk, which contains up to 20% fat, protein - 10.5%, vitamins 3 times more than in cow's milk. Women's milk contains 1.25% protein, therefore, cow's and any other milk requires dilution when feeding infants. According to the nature of the proteins, the milk of various animals can be divided into casein (casein 75% or more) and albumin (casein 50% or less). Casein milk includes the milk of most lactating farm animals, including cows and goats. Albumin milk includes mare and donkey milk. The peculiarities of albumin milk are its higher biological and nutritional value, due to the better balance of amino acids, high sugar content and the ability to form small, tender flakes when soured. Albumin milk in properties approaches women's milk and is the best substitute for it. Albumin particles are 10 times smaller than casein, the particles of which are larger even when curdling in the stomach baby cow's milk protein forms hard-to-digest large, dense, coarse flakes.

The main protein in cow's milk is casein, which in milk is 81.9% of the total amount of milk proteins. Lactoalbumin is found in milk in the amount of 12.1%, lactoglobulin 6%. Milk fat is one of the most valuable fats in terms of nutritional and biological properties. It is in a state of emulsion and a high degree of dispersion. This fat is highly taste properties. Milk fat contains phospholipids (0.03 g per 100 g of cow's milk) and cholesterol (0.01 g). Due to the low melting point (within 28-36? C) and high dispersion, milk fat is absorbed by 94-96%. As a rule, the fat content of milk in autumn, winter and spring is higher than in summer. With good animal care, the amount of fat in cow's milk can reach 6-7%. Carbohydrates in milk are in the form of milk sugar - lactose. It is the only milk carbohydrate found anywhere else. Lactose refers to disaccharides; upon hydrolysis, it breaks down into glucose and galactose. The intake of lactose into the intestines has a normalizing effect on the composition of the beneficial intestinal flora. Milk intolerance, noted in many people, is caused by the absence in the body of enzymes that break down galactose.

Milk sugar is of great importance in the production of lactic acid products. Under the action of lactic acid bacteria, it turns into lactic acid; while curdling the casein. This process is observed in the production of sour cream, curdled milk, cottage cheese, kefir.

Minerals. Milk contains a wide range of macro- and microelements. In the mineral composition of milk, calcium and phosphorus are of particular importance. It also contains potassium, sodium, iron, sulfur. They are found in milk in an easily digestible form. Microelements contain zinc, copper, iodine, fluorine, manganese, etc. The calcium content in milk is 1.2 g/kg.

Vitamins. Almost all known vitamins are present in milk in small quantities. The main vitamins of milk are vitamins A and D, and also contain some amounts of ascorbic acid, thiamine, riboflavin, nicotinic acid. In summer, when animals eat juicy green fodder, the content of vitamins in milk increases. The calorie content of milk is low and averages 66kcal per 100g of product. Milk contains a number of enzymes.

Milk causes a weak secretion of the gastric glands and is therefore indicated for peptic ulcer and hyperacid gastritis. Due to the presence of lactose, when drinking milk, a microflora develops in the intestines, delaying putrefactive processes. There is little salt in milk, and therefore it is recommended for people suffering from nephritis and edema. There are no nucleic compounds in milk, therefore, it is indicated for persons with impaired purine metabolism. For febrile patients, milk is both light food and drink.

One of the most common health disorders in old age is a disease of the blood vessels - atherosclerosis. Among the nutrients that have a preventive and therapeutic value in atherosclerosis, vitamins A, E, B vitamins, choline and the amino acid methionine should be especially noted. All these substances are found in milk.

The overall balance of all substances that make up milk is characterized by an anti-sclerotic orientation, which has a normalizing effect on the level of cholesterol in the blood serum.

Due to the easy digestibility of milk, it is widely used in the treatment of patients with gastric ulcer, gastritis with high acidity of gastric juice. In recent years, a favorable effect of milk on the nervous system has been established. The famous Russian doctor S.P. Botkin believed that milk is a precious remedy in the treatment of diseases of the heart and kidneys. Milk protein promotes better liver function in healthy person, and is also used in clinical nutrition for liver diseases, infectious diseases, etc.

The value of lactic acid products also lies in the fact that lactic acid bacteria prevent the development of putrefactive pathogenic bacteria in the intestines. Therefore, these products are widely used in preventive and medicinal purposes in diseases gastrointestinal tract.

Milk plays an important role in the nutrition of a pregnant woman, as the most perfect source of providing the body with the “building material” necessary for the normal development of the fetus. During breastfeeding, the mother's milk supply provides the child with the necessary substances.

Physiological norms daily ration(only 3000-3200 calories) include the consumption of 400-500 g of milk (fresh and sour), 25-30 g of cottage cheese, 15-20 g of cheese and 15-20 g of sour cream on average. milk and lactic acid products should receive a much wider application than is currently available in the daily diet of an adult.

“Milk,” wrote academician I.P. Pavlov, “is an amazing food prepared by nature itself.” It has been established that this product contains over a hundred of the most valuable components. It includes all the substances necessary for the life of the body: proteins, fats, carbohydrates, mineral salts, vitamins. These components of milk are well balanced, making them easily and completely digestible.

Milk, like bread, mankind began to use in writing more than five thousand years ago. Milk is the only food product in the first months of human life. Importance it has in the diet of an adult. For old, weakened and sick people, milk is an indispensable food.

Since ancient times, milk has also been used as a remedy for many diseases in the treatment of the heart, kidneys and other organs.

The inclusion of dairy products in the diet increases its usefulness and promotes better absorption of all components.

Milk has a beneficial effect on the secretion of the digestive glands. For its assimilation by the body, energy is required 3-4 times less than for the assimilation of, for example, bread.

From cows of the same breed, depending on climatic conditions, feeding, maintenance, different amounts of milk are obtained, its quality is also different. The composition of milk varies depending on the time of year, the age of the cow, her individual features and many other factors. Employees of the All-Union Scientific Research Dairy Institute (VNIIMI) conducted a study of milk supplied to 220 dairy enterprises in 55 zones of the RSFSR and 12 union republics. In total, about 80,000 samples of milk were studied, accounting for about 25-30% of its total procurement in the studied areas. The studies were carried out monthly. With an average fat content in milk of 3.55%, the fluctuations were in the range of 3.36-3.86%, i.e., at the level of existing basic indicators. The amount of total protein was 3.13% with fluctuations from 2.96 to 3.30%. The density of milk averaged 1.0283 (23.3%) with fluctuations from 27.4 to 29.4%. The content of solids in milk on average turned out to be 11.93% with fluctuations from 11.60 to 12.36%.

In addition to cow's milk, milk and other types of farm animals are used for food, and both in whole, and in the form of dairy products: cheese, made mainly from sheep milk, koumiss - from mare.

1. Nutritional value of milk

biological value

the most important integral part milk are proteins, the total amount of which in cow's milk averages 3.2% (2.7% - casein and 0.5% - whey proteins - albumins and globulins). Half a liter of milk is almost 1/3 of a person's daily requirement for animal protein. According to the balance of amino acids and digestibility, milk proteins are among the most valuable. They have practically no amino acids that limit biological value. True, there is some deficiency of sulfur-containing amino acids (mainly cystine) in casein, but they are rich in whey milk proteins, which are characterized by a high content of the other two most deficient amino acids - lysine and tryptophan, often deficient in human diets. Milk proteins, under the influence of hydrochloric acid and digestive enzymes produced in the stomach, coagulate into small flakes, which greatly facilitates their digestion and assimilation. Whey proteins are especially well absorbed. The digestibility of milk proteins is 96--98%. It should be noted that it is whey proteins that are carriers of special protective factors - immunoglobulins, which are involved in the production of antibodies against pathogens and viruses.

From caseins in the process of digestion, physiologically active peptides are formed, one of which, the so-called casein glycomacropeptide, inhibits gastric secretion and motility. In the process of digestion of cow's milk, peptides with opioid (narcotic) activity (β-casomorphins) can be released, which have a regulatory effect on cerebral circulation. Substances have been isolated from bovine casein that reduce blood pressure Therefore, milk, dairy products and dishes from them are used in the complex treatment of coronary heart disease, atherosclerosis of the coronary, cerebral, peripheral vessels, stage II-III hypertension. In addition, food peptides isolated from milk casein can be used as promising medicines for the treatment of gastroduodenal pathology associated with hyperfunction of the stomach, to reduce the feeling of hunger and as anti-stress drugs. However, there is scientific evidence that milk casein increases blood cholesterol levels and promotes atherosclerosis. Therefore, abuse dairy products, especially fat-free cottage cheese, consisting of almost pure casein, is not worth it.

Compared to other fats of animal origin, milk fat is better absorbed in the human body, which is facilitated by relatively low temperature its melting (28--33 °C) and finely dispersed state. The digestibility of milk fat is 97--99%. It contains relatively few essential polyunsaturated fatty acids, but when drinking half a liter of milk, about 20% of a person's daily need for them is covered. The presence in milk fat of deficient arachidonic acid, short-chain fatty acids (in total, milk fat includes more than 30 different fatty acids), as well as significant amounts of phospholipids and vitamins A and D, increases its biological value. In addition, the ratio of fat and protein in milk is close to optimal (1:1). Milk, especially fat, is a weak causative agent of gastric secretion and motility, has a pronounced antacid effect, that is, it directly interacts with hydrochloric acid in the stomach, inactivating it. Therefore, it is recommended to use milk for hyperacid (with high acidity) gastritis, gastric ulcer and duodenal ulcer.

Due to the fact that fats slow down the evacuation from the stomach, inhibit gastric secretion and cause a feeling of satiety, for more fat milk less gastric juice is secreted at the beginning of digestion and it lingers longer in the stomach. Therefore, full-fat milk (and cream) has a more pronounced therapeutic effect in these diseases than fat-free.

Carbohydrates in milk are represented mainly by lactose (milk sugar), the amount of which is on average 4.5--5%. Unlike other sugars, it is relatively poorly soluble in water, is slowly absorbed in the intestine, stimulates the development of lactic acid sticks in it, which, by forming lactic acid, suppress putrefactive microflora and contribute to better absorption of calcium and phosphorus. Lactose is 5-6 times less sweet than sucrose (beet sugar), so milk does not have a pronounced sweet taste. Under the influence of enzymes of the stomach and intestines, lactose is broken down into glucose and galactose, which are absorbed into the blood and serve as a source of energy. The role of lactose in the nutrition of infants is especially important.

However, children and adults may have milk intolerance (the so-called selective lactose malabsorption), associated with a deficiency of the intestinal enzyme lactase, which leads to impaired digestion of milk sugar, its fermentation in the gastrointestinal tract, accompanied by bloating, abdominal pain and other phenomena. indigestion. Moreover, primary lactase deficiency is a genetically determined condition and depends on belonging to different ethnic groups. So, lactase deficiency occurs in 15-20% of adult residents of Northern and Central Europe and in 75-100% of indigenous peoples of Northern and South America, Africa, Southeast Asia. In Russians, the frequency of lactase deficiency is 12.5-16.3%, in Belarusians - 13%, in Ukrainians - 5.8%.

It should be noted high content in milk and dairy products such mineral elements as calcium and phosphorus. Both of them are found in milk in well-balanced proportions, which determines their relatively high digestibility. Thus, the ratio between calcium and phosphorus in milk is 1:1 - 1.4:1 (in cottage cheese and cheese - 1: 1.5 - 1: 2), while in meat and fish it is equal, respectively, 1:13 and 1:11. About 80% of a person's daily calcium requirement is met by milk and dairy products. At the same time, milk is relatively poor in some trace elements: iron, copper, manganese, iodine, and fluorine. Therefore, when eating predominantly dairy products, especially children, anemia may develop. Milk and dairy products are a constant source of almost all vitamins. They are especially rich in riboflavin, which is relatively deficient in food products; about 50% of a person’s daily requirement for this vitamin is met by milk and dairy products.

The biological value of milk is supplemented by a variety of enzymes, hormones, antibodies, antibiotics and other biologically active substances. Thus, the nutritional and biological value of milk is indisputable, and it is an indispensable human food product. However, not everything is so perfect with milk: it is low in iron, which even calves replenish with grass; for those who, starting from infancy add cow's or goat milk, more often develop diathesis, anemia, dysfunction of the gastrointestinal tract. In addition, as I.P. Neumyvakin points out, casein (protein) contained in mother's milk is broken down using the so-called rennet, and when the need for casein disappears (the foundation for the formation of nails and hair is laid) - and this usually happens at 1-2 years of age - it disappears. In addition, milk, entering the stomach, under the influence of acidic contents, coagulates, forming, as it were, cottage cheese, envelops particles of other food and isolates it from gastric juice. And until curdled milk is digested, the process of processing other food will not begin, which is why milk should be drunk separately from other food.

Energy value and digestibility

biological The value of milk is that:

Its components are well balanced

They are easily digestible

Milk components are mainly used for synthetic and "construction" (plastic) purposes.

The amino acids of milk are so well balanced that its proteins are digested by 98%. According to this indicator, they are inferior (and only by 2%) to egg proteins, the amino acid balance of which is accepted by the World Health Organization (WHO) as a standard (100%). In addition, some substances necessary for the body are found only in milk. Let us name only the deficient arachidonic acid and the biologically active protein-lecithin complex. Both of these components prevent the development of atherosclerotic processes in the body.

Milk calcium is the most easily digestible calcium in nature. The complex of vitamins A, B2, D3, carotene, choline, tocopherols, thiamine and ascorbic acid is exceptionally favorably balanced in it. All this has a normalizing effect on the level of cholesterol in the blood serum.

The composition of the mineral substances of milk includes all the elements of the periodic system of Mendeleev. It contains salts of potassium, sodium, magnesium, iron, citric, phosphoric and hydrochloric acids and a number of others. All of them are found in milk in an easily digestible form.

Milk contains carbohydrates, fats, proteins and mineral salts in the greatest quantity. Vitamins, enzymes, trace elements, hormones, immune bodies and other substances are contained in milk in very small quantities, but they have high biological activity and their role in human nutrition is enormous.

Milk and dairy products are essential food products. They are the main products of dietary and clinical nutrition and differ from other food products in that they contain all the substances necessary for the body in an optimally balanced state. Milk provides normal growth, development and vital activity of the organism. High nutritional, biological and medicinal properties milk has long been valued; in ancient times, milk was given names such as “juice of life”, “ White blood”, “source of health”, etc.

The great Russian physiologist I.P. Pavlov viewed milk as amazing food prepared by nature itself and characterized by easy digestibility and nutritional value. The digestibility of milk and dairy products in the human body is 95-98%. The inclusion of dairy products in any diet increases its usefulness and quality indicators, promotes better absorption of other components.

Physiological value(FC) - the ability of food components to activate the activity of the main body systems. FC is provided by physiologically active substances (PAS).

Depending on the effect on the human body, physiologically active substances can be divided into the following groups:

1. PAS, which have a stimulating effect on the human nervous system. These include alkaloids: nicotine, caffeine, theobromine, as well as ethyl alcohol.

2. PAS affecting cardiovascular system. This group includes minerals, potassium, magnesium, calcium; vitamins B1, PP,

3. FAV, activating the digestive system. Include minerals: sodium, chlorine, enzymes, phospholipids, vitamins, fiber, hemicelluloses, pectin, aromatic substances, glycosides, nitrogenous and nitrogen-free extractives, hop resins and acids.

4. PAS that enhance the immune system. These include substances with a pronounced bactericidal and fungicidal action: polyphenols, dyes, aromatics, vitamins: B 1 , PP, glycosides, organic acids, among which benzoic, salicylic, gallic, citric, and lactic acids are distinguished by the greatest bactericidal activity.

5. PAS, which contribute to the removal of harmful substances from the body: toxins, toxic elements, bacterial etc. poisons. This group is represented by pectins, fiber, and some proteins.

It should be noted that substances that are of no value to the human body (for example, bacterial and fungal toxins) are considered harmful, as well as useful material, which have a negative impact on the human body in doses exceeding the MPC.

The above list of PAS belonging to different groups indicates that many food substances are multifunctional.

Nutraceutical components in milk favorably affect the human body: calcium, lactoferrin, lactoperoxidase, immunoglobulins, whey proteins, linolenic acid, oligosaccharides, phospholipids, etc.

There are many more nutraceutical components in colostrum, and some of them are present in much higher concentrations than in regular milk.

Milk and dairy products are extremely valuable and indispensable products in the prevention and treatment of diseases such as gastrointestinal, diseases of the heart and blood vessels, liver, kidneys, diabetes, obesity, acute gastritis, etc. They should be consumed as part of a balanced diet to maintain tone and as a factor in increasing life expectancy.

Dairy products are of exceptional importance in the nutrition of children, especially in the initial period of their life, because. contains a significant amount of phospholipids, essential amino acids, normalizing the processes of growth and development of the body.

The physiological value of milk increases significantly when consumed in the form of fermented milk drinks. Their use contributes to the creation of an acidic environment in the intestinal tract and, as a result, the suppression of putrefactive microflora and the normalization of digestion. Therefore, dairy products are widely used as medicinal products with intoxication of the body with toxic products of putrefactive microflora. Dairy products are digested much easier and faster than milk. In addition, they contain a large number of antibiotic substances that have a bactericidal effect.

Milk (in the amount of 1 liter) satisfies the daily human need for animal fat, calcium, phosphorus; 53% - in animal protein; by 35% - in irreplaceable fatty acids and vitamins A, C, thiamine; 12.6% in phospholipids and 26% in energy.

Due to its unique chemical composition, dairy products can replace all other food products. The chemical composition of milk and dairy products is extremely diverse, and all of their components are essential in nutritional physiology.

Dairy products contain water, proteins, fats, carbohydrates, minerals, vitamins, organic acids, dyes, immune bodies, enzymes, gases, etc. chemical composition various factors influence: type of animal, age, feeding and keeping conditions, season, etc. (Table 2)

table 2

The chemical composition of cow's milk

Protein substances of dairy products. They are the most nutritionally valuable part of dairy products, they consist of casein and whey proteins - albumin and globulin. In addition to them, dairy products contain shell proteins of fat globules and some other little-studied protein substances, as well as nitrogenous compounds.

Squirrels dairy products have an extremely favorable quantitative and qualitative composition of amino acids, including all essential amino acids. Therefore, dairy proteins are considered complete. In addition, milk proteins, unlike other animal proteins, are relatively easily reproducible and are recognized as the cheapest, which allows them to be used more and more widely every year as food additives to non-dairy products.

Milk protein surpasses the ideal protein in amino acid composition, which determines its high physiological value(see table 3).

The nutritional value of milk and products prepared on its basis determines its importance in children's and diet food. By including such foods in your diet, you will saturate the body with calcium and other valuable substances. Milk makes a person healthier and more beautiful.

What is nutritional value?

If you are interested in certain characteristics of products, you should know for sure what they mean. Yes, nutritional value is complete list properties that satisfy the physiological needs of the body. Most often, this concept means the content of proteins, fats and carbohydrates in every 100 grams of products.

It is also worth noting the importance of such an indicator as biological value. It characterizes the compliance of the amino acid needs of the human body. Speaking of energy value, it is worth noting that this is the number of calories that are released during the processing of the product by the body.

Milk: chemical composition and nutritional value

Milk is the first human food, which gives the body everything it needs from birth. Due to the rich chemical composition, it is possible to maintain the active vital activity of the body. So, milk contains the following substances:

• proteins;
• fats;
• milk sugar;
• mineral salts;
• water.

It should be noted that this is a basic set of components that cannot fully characterize milk. The chemical composition and nutritional value can vary greatly, depending on the origin of the product, as well as the way it is processed.

If we consider in more detail the proteins contained in milk, they are represented by albumin, globulin and casein. The latter is involved in the formation of glycopolymacropeptide, which increases the absorption of other components. All proteins are characterized by easy absorption and contain all the amino acids necessary for the body.

Fats in milk are contained in the form of tiny particles. It is they who form everyone's favorite cream. Milk fat is 96% absorbed by the body, due to its high dispersion. Its content in the product depends on the season (in summer this figure decreases), as well as the quality of animal care.

Considering such an indicator as the nutritional, energy value of milk, one cannot but say about the carbohydrate component. It is represented by lactose. Precisely the presence this component due to the possibility of preparing fermented milk products.

The nutritional value of milk is determined high content vitamins. The main ones are A and B. B a small amount present ascorbic acid, nicotinic acid, riboflavin and thiamine. The highest concentration of vitamins in milk is observed in the summer. Also, this indicator can be affected by the method of processing and storage conditions.

More about vitamins

As already mentioned, the nutritional value of milk and dairy products is largely due to the increased content of vitamins in them. So, if we take a closer look at the chemical composition, we can note the presence of the following useful components in it:

Different types of milk

The nutritional value of milk is largely determined by its origin. So, deer is considered the most nutritious. The concentration of proteins and fats reaches, respectively, 11% and 20%. As for the vitamin component, it is three times more saturated than in the case of cow's milk.

The nutritional value of milk is largely determined by the nature of the proteins that it contains. So, most farm animals (including cows and goats) give casein milk. And, for example, mare and donkey is albumin. Since it is most similar in composition to mother's milk, such milk is an ideal substitute for breastfeeding. Albumin particles are several times smaller than casein, and therefore we can talk about its good digestibility.

Whole milk

Despite the fact that milk is one of the most common products that has been known since childhood, not everyone thinks that there are several types that are characterized by certain indicators. So, for starters, you should pay attention to whole milk. The nutritional value, in this case, will be the highest, because the product has not been subjected to any processing. An exception may be the straining process, which is carried out immediately after milking.

Whole milk contains the largest amount of vitamins and minerals. There is also a high concentration of calcium, which is almost completely absorbed by the body. This product is credited with strengthening immune system, normalization of the nervous system, elimination of heartburn, acceleration of metabolism.

However, there are a number of skeptical claims about whole milk. Given its high fat content, it is not suitable for feeding children. And in adulthood, not everyone tolerates this product well. So, according to the latest data, one sixth of the world's population suffers from lactose intolerance. Whole milk is an allergen, and can also cause dangerous infections.

Skimmed milk

The desire for harmony makes people buy products marked "0% fat". This trend has also affected milk. The amount of fat in it does not exceed 0.1%. In fact, this is the so-called reverse, which is obtained by separating cream from milk. Buyers should be interested most of This milk is not sent to the store shelves, but back to the farms to feed the animals.

Do not place high hopes on a product such as skimmed milk. Its nutritional value is negligible. Carbohydrates and proteins, respectively, 5% and 3%. Calorie content is characterized by an indicator of 35 kcal. At the same time, such milk is characterized by a rich vitamin and mineral composition. Nevertheless, doctors do not recommend using it on an ongoing basis.

It is worth paying attention to the manufacturing process. Nutritional value of dry skimmed milk significantly reduced during processing. When the fat component is removed, vitamins A and D are almost completely removed from the product. Thus, the proteins and calcium that remain in the milk are not absorbed by the body. At frequent use skimmed and powdered milk, the body's own resources are depleted.

Powdered milk: nutritional value

In conditions big city not always found natural product. In addition, people tend to give known substances a more convenient form, such as powder. A good example can be powdered milk. The nutritional value this product the same as the original. But for this you need to prepare the so-called reconstituted milk. To do this, the powder is diluted in water (1: 7). At the same time, it is quite possible to cook from such milk homemade kefir, cottage cheese and other useful products.

The nutritional and biological value of milk is preserved thanks to a special manufacturing technology. Fast drying is carried out, and the temperature does not exceed 40 degrees. Thus, all useful substances are preserved. And thanks reduced content moisture (no more than 6%), provided long-term storage product.

Nutritional value of condensed milk

It is worth admitting that few people are interested in such a question as nutritional value. For most people, this favorite treat. Nevertheless, condensed milk is not only tasty, but also very useful product. To begin with, it is worth noting the high protein content in this product. Its concentration can reach 35%.

In fact, condensed milk is evaporated cow's milk. The nutritional value of the final product is slightly lower, but in general it is no less useful. Condensed milk is completely absorbed by the body, saturating it with calcium and phosphorus. Thus, by regularly consuming this product, you can strengthen the health of bones, eyes and enhance mental activity.

However, condensed milk should not be abused. The fact is that it contains a significant amount of sugar, which causes high calorie content(328 kcal) and a significant carbohydrate component (55.5 g). A large number of The product contributes to the development of obesity, diabetes and caries.

Dairy products

The composition and nutritional value of milk make this product one of the most popular. However, in pure form few people love him. Most people prefer dairy products. They not only preserve the benefits of milk, but also have a beneficial effect on work. digestive system. So, you should especially pay attention to the following products:

• Kefir is made from pasteurized milk. A special leaven is added to it, after which the fermentation process begins. The nutritional value of this product depends entirely on the quality of the milk. If use whole product, then the protein component accounts for almost 3%, the concentration of fats 3%, and carbohydrates 4%.
• prepared from a pasteurized product using bacterial cultures. It will contain approximately equal amount fats and carbohydrates (about 3%) and 10% carbohydrates. Given the low acidity of the product, it is actively used in artificial feeding children.
• Belakt is also fermented milk product produced using bacteria. It has a high content of enzymes. Another feature of the product is the presence in the composition of substances that, in their properties, resemble antibiotics.
• "Narine" is a fermented milk product that came to us from Armenia. There it is actively used for breastfeeding. Due to the special bacteria contained in the sourdough, the acidity index is quite low. And, getting into the body, "Narine" activates the production of a substance that suppresses pathogenic microbes. Proteins and fats in the product account for 3% and 4%, respectively, and carbohydrates - just over 6%.
• Kumis is traditionally made from mare's milk. Nevertheless, recipes adapted for cow's are known. In milk, starter is added, which contains bacteria and yeast. The nutritional value largely depends on the quality of the base and the degree of maturity. It can contain up to 3% protein, up to 1% fat and 6% carbohydrates. The product is useful for digestion, and also has a tonic effect.
• Yogurt is not just a popular fermented milk product, but also a delicacy loved by everyone. In ancient times, it was prepared exclusively from To get yogurt, you need to add the so-called Bulgarian stick to the base. Average calorie content finished product characterized by an indicator of 57 kcal. Proteins, fats and carbohydrates it contains, respectively, 4%, 2% and 6%. These figures may vary, depending on the type of milk and the method of processing. It is worth noting that only pure yogurt, which does not contain dyes and flavoring additives, has exceptional benefits.

Other popular products

Since ancient times, people have been interested in such a question as the nutritional value of milk. A great variety of dairy products are prepared on its basis. Nevertheless, there are a number of popular ones that are almost always present on the table, namely:

• Cottage cheese is one of the most valuable food products, which is characterized by a high protein content (about 14%). Its preparation is based on processes. Curd is characterized by high acidity. But this indicator decreases with an increase in the level of fat content of the product.
• The process of making cheese is based on the precipitation of casein. Depending on how the milk is processed, the product can be hard, soft, brine or melted. The protein component can reach 30% (as well as fat).
• Sour cream is a product made from pasteurized cream. It is quite fatty (this figure can reach 40%).

Milk quality

The high nutritional value of milk proteins determines the popularity of this product. Nevertheless, only what is of high quality is useful for the body. The characteristics of milk largely depend on how the processing was carried out.

The milk that entered the plant is first of all checked by organoleptic index. If it turned out to be in accordance with the standards, it is carefully filtered to remove impurities. Next, the fat content is normalized by adding skim milk or cream.

The most important are the stages of pasteurization and sterilization. These processes are necessary for the destruction of pathogens, as well as a number of enzymes. Thus, it is possible to get safe product, which is characterized by long-term storage.

Pasteurization is carried out by prolonged heating. As a result, milk changes its natural taste. It is also worth noting the decrease in the concentration of calcium in the product.

Is milk dangerous for humans?

The nutritional and biological value of milk makes this product one of the most useful. Nevertheless, it is worth mentioning the danger that it carries. Milk can serve as a source of dangerous infectious diseases. In this case, viruses can get into the product from the animal and during processing.

Viruses can be found not only in milk, but also in products prepared on its basis. This increases the incubation period of the bacteria. So, the most dangerous diseases transmitted through milk are the following:

• Foot and mouth disease is a viral disease that affects the mucous membranes and respiratory tract. It appears in the form of blisters and ulcers. The virus of this disease is resistant to heat. To get rid of it, you need to boil the milk for at least 5 minutes.
• Brucellosis is a disease that affects almost all body systems. Its danger lies in the fact that initial stage it is almost asymptomatic. Milk from animals infected with brucellosis is subjected to prolonged boiling followed by pasteurization.
• Tuberculosis - affects mainly the respiratory system. If such an infection is found in an animal, then milk is strictly forbidden to be eaten.
• Other dangerous infections are anthrax, rabies, hepatitis, plague, and others. Animals with such diseases are subject to destruction with the obligatory presence of a sanitary doctor.

Conclusion

From the very first days of human life, it is milk that supplies the body with all the necessary nutrients and vitamins. Thus, the benefits of this product are undeniable. To maintain bones, digestive, nervous and other body systems in optimal condition, milk simply must be present in the diet. It is important to choose quality product, and whole or fat-free should be treated with caution.

At the moment, there is a wide range of dairy products on the market, which are also characterized by high nutritional value. Among them, you can often find many copies marked "Farm" or "Rustic". Contrary to fashion trends, such products should be treated with extreme caution, because in milk that has not been exposed to heat treatment and pasteurization, may contain viruses that are dangerous to humans.