What is whole cow's milk made of? Contraindications and harm of milk
Milk is loved and known all over the world. It is used in the human diet different ages, but there are scientists who claim that the drink is unhealthy. Despite such loud statements, his fans are not getting smaller, since milk has unique composition and is an ingredient for the manufacture of butter, cheese, dairy products.
Product properties
Milk has been used by man since ancient times, and it has always been believed that it only has a beneficial effect on the body. Although the benefits of the drink are increasingly being questioned, few people are ready to completely eliminate the product from their diet.
Milk can be obtained not only from a cow, it is also given by a horse and a goat, each drink is different in its composition. The most commonly used in the diet is the milk of large cattle. The composition often depends on the health of the animal and what it eats. The production of a drink on an industrial scale has been put on a large stream, as independent product it is used by about 80% of the world's population, the rest prefer to eat derived products.
The composition contains 3.2% proteins, so the product is nutritious. Each farmer keeps track of this indicator, as it is important for assessing the quality of the drink. It is the protein contained in milk that is absorbed by the human body by 95%. Its peculiarity lies in the fact that there are essential amino acids, the absence of which leads to metabolic disorders.
Methionine is responsible for the metabolism of fat cells, it helps prevent degeneration of a very important internal organ- liver. For the synthesis of serotonin - the hormone of happiness - there is tryptophan in milk, the lack of which leads to such serious problems like diabetes, cancer and even tuberculosis.
There is also a component such as lysine, which is responsible for the normal composition of the blood. When it is deficient, a person develops anemia, muscular dystrophy, the lungs and liver stop working normally, the bones suffer from a lack of calcium.
Casein, which is found in cow's milk, is represented by two forms:
- alpha - can cause allergic reactions;
- beta - well absorbed.
Long-term studies have shown that the drink is simply indispensable for humans. No other product can compete with it in terms of the number of useful elements. Those who have problems with the work of the heart should definitely eat this product, since the lactose found there helps to improve the condition.
Speaking specifically of lactose, then there are those who have an acute intolerance to it, so they cannot consume the product. As a rule, those who have problems with digestion suffer from intolerance, therefore it is recommended to consume fermented milk products.
Vitamin B12 contained in milk has a positive effect on the human body. He helps psycho-emotional state a person and even soothes, so before going to bed it is advised to drink a glass of warm drink with a spoonful of honey.
Athletes should not exclude the product from the diet, for whom it is a rich source of energy due to the fats and proteins in the composition. The product has a positive effect on growth muscle mass, skeleton.
Despite such a number of useful elements, fat milk useful not for everyone, therefore, on the shelves you can find product options that differ in this indicator. It can be in the range from 1 to 5%. It is possible to adjust the fat content on an industrial scale, increase the percentage by adding cream, and reduce by skimming.
An allergy can be not only to milk itself, but also to casein. There are scientists who gave examples when the use of this drink caused an increase in acidity in the gastric juice, resulting in an ulcer. But there are those who boldly assert today that cow's milk, when consumed regularly, leads to the formation of malignant tumor. However, to name specifically the component that contributes to the development cancer cells while no one can.
The quality of the product is negatively affected by the attitude towards animals on the part of manufacturers, who often administer antibiotics and hormones in order to achieve the desired results. All this negatively affects the drink that we have to eat.
That is why, if it is possible to buy milk from a farmer who grazes an animal in the fields, it is better not to put off this decision. True, it is worth knowing that the animal is healthy, and not too lazy to pasteurize the product. This will not affect its benefits, but you can protect yourself from diseases that are transmitted through milk.
Kinds
Milk is different taking into account the features of modern production, namely:
- whole;
- pasteurized;
- ultra-pasteurized;
- sterilized.
A natural product without any additional processing is called whole. You can buy it directly from cattle breeders, since it is not commercially sold on an industrial scale.
Pasteurized is processed by temperature, but it is not boiled, only heated to a maximum of 80 degrees. The pasteurization process can be long, for half an hour, but at a temperature not higher than 65 C, or it can be short or even instant. The higher the drink is heated, the less time it is processed, since it can lose all its useful qualities. UHT is heating the product to 150 degrees for two seconds.
A completely different type of beverage processing is sterilization. Over a hundred degrees, milk boils for more than half an hour. The goal is not to preserve useful elements, but to extend the shelf life. On average, in the refrigerator, such a product can be and be edible for thirty days. It is for this reason that sterilized milk becomes the most sought after, especially on hot days. It is well transported, which is important for residents of distant regions.
Chemical composition
Homemade cow's milk has biological activity and consists of vitamins, carbohydrates, fats, proteins. In fact, the mineral composition is very rich, therefore, the benefits of it cannot be disputed. Few people know that 87.5 percent of this drink is water, and all the rest useful elements, including the calcium content, are concentrated in the remaining percentages.
It was possible to determine this only in the process laboratory research when the sample was dried at a temperature of 105 degrees. dry residue and was studied in detail by scientists who wanted to understand more chemical composition and the amount of nutrients in 100 grams of the product. If at least 9% of the total mass dry skimmed milk residue, then this is high-quality milk. This is how producers are recognized who dilute the product for sale with water in order to increase income.
Among other things, the drink contains great amount essential vitamins different groups:
An important component is beta-carotene and acids, including:
- ascorbic;
- nucleic;
- fatty;
- amino acids.
Admission to regular basis helps a person control cholesterol levels and get the calcium necessary for bone development. For this reason, milk is given to children, because they musculoskeletal system needs support.
Among the useful trace elements:
- chlorides;
- magnesium;
- potassium;
- phosphorus.
The chemical composition of the product will vary depending on the time of year, conditions of keeping, age and quality of animal food.
This is interesting, but only humans eat the milk of other mammalian species. BJU balance on a glass of milk plays important role in determining the quality of a product.
Since milk is produced by the cow to feed the calf, the human body cannot absorb all the trace elements from it. If for an animal the balance is optimally selected, then for a person it is not. This is one of the reasons why scientists began to think about real benefit product.
Cow's milk proteins contain casein, on average it is 80%, the remaining 20% is whey protein. In newborns, they can fully satisfy the body's need for amino acids, this is the main value of the product. You need to understand that different types contain in breast milk a certain proportion of casein and whey proteins. If we consider in more detail cow, goat and even sheep's milk, then there is more casein, which is why it is called so. But albumin-globulin has more protein whey. This is the case with humans, horses and donkeys.
By the way, the breed of livestock also affects the ratio of trace elements in the composition of the product. Therefore, some are considered dairy, while others are meat.
The nutritional value
The nutritional value of the drink is its most important indicator. For a visual representation, scientists even compiled a table where it is indicated percentage proteins, fats and carbohydrates.
BJU looks like a glass of milk in the following way:
- 88 g of water;
- 3.2 g proteins;
- 3.25 g fat;
- 5.2 - carbohydrates;
- 0.35 - vitamins and elements.
The average percentage of fat content should be at least 3.5%. Since the drink is used as the main raw material for creating other products, the quality of cream, sour cream and even cottage cheese will depend on this indicator.
about twenty various acids included in cow's milk. The pour point is 28 degrees. It is worth saying that fat has a low specific gravity, so it accumulates on the surface in the form of cream.
They include great content vitamins such as:
That is why the milk that is obtained on farms, not sterilized to extend the shelf life, but consumed only in a pasteurized state, has a beneficial effect on a person, strengthening his body, enriching him with essential microelements.
The low calorie content of the product will please, only 62 kcal. This indicator plays an important role in the demand for the product on modern market. You can use drinks based on this component for people who monitor nutrition. Nutritionists have a positive attitude to the regular use of the product, not only in fresh, but also in sour form.
If you are one of those body watchers, then cow's milk should be in your diet, unless you are allergic to casein. Cooking has learned how to use the drink in different ways and create many dishes from it. Even infant formulas are produced commercially using this indispensable product.
You can get the product only on an industrial scale, using special installations where moisture evaporates from milk. To use the mixture in the future, it is diluted with water in the proportion described on the package. In this form, nutrition for a child has the same useful qualities the same as whole milk.
The product first appeared on store shelves in the 19th century. The main consumers were the northern regions of the country, since delivering natural product, unsterilized, with the preservation of all useful properties, it was impossible. It is important to understand what is useful powdered milk remains only under one condition - the manufacturer strictly observed the technology, using high quality raw materials.
In conclusion, I would like to say that cow's milk is loved in different countries, regardless of age. Despite the attempts of scholars to express their negative attitude to the drink, more and more fans of this product appear. In terms of composition and properties, it is unique and cannot be replaced by anything else, therefore, in the absence of intolerance, it would be reckless to exclude milk from the child's diet.
You can’t forbid using it, because the product helps to create a huge number of fermented milk products, the use of which also has a positive effect on the human body. Modern technologies allow you to create products that can please their palatability. Without milk, kefir and fermented baked milk, yoghurts and ayran will disappear from the shelves.
The main thing you should pay attention to is quality, only this and nothing more.
On the dangers and benefits of milk, as well as its calorie content, see the following video.
Cow milk is the most common type of milk, which is produced worldwide on an industrial scale. It has pleasant taste and aroma, as well as a white uniform color.
Kinds
The lactation period in cows is quite long. It is 305 days. There are three stages in this:
colostrum: 7-10 days after calving
normal milk release period: 280 days
old milk release period: 7-14 days before the end of the lactation period.
Colostrum and old milk differs from normal milk in its physicochemical, organoleptic and technological characteristics.
Compound
Milk contains a huge amount of substances useful for the human body. Moreover, they are in an easily digestible form and optimal ratios. Cow's milk contains proteins, fats, carbohydrates, mono- and disaccharides, organic acids, vitamins - retinol, betacarotene, ascorbic acid, E, B1, B2, B9, PP, micro and macro elements - potassium, calcium, sodium, iron, magnesium, cobalt, copper, fluorine, manganese, iodine, phosphorus, zinc, etc. In total, it contains more than 50 elements.
Application
Milk is consumed in pure form, on its basis, numerous fermented milk products, cheeses are made. It is also included in many dishes, cocktails.
Beneficial features
Determined that milk protein is easier to digest by the human body than the protein of meat and fish.
400 grams of milk per day provide daily requirement human body in calcium.
Milk has a beneficial effect on the vital activity of the intestinal microflora, strengthens skeletal system and teeth, has a positive effect on the condition of hair and skin, helps with kidney diseases, anemia, tuberculosis, disorders of the nervous system, prevents the development cardiovascular disease maintains vascular elasticity, reduces arterial pressure, relieves heartburn, has an immunomodulatory effect, facilitates well-being with migraines.
If you drink it before bed, it has a calming effect. When used in the morning - relieves drowsiness and gives strength.
Use restrictions
Some people are lactose intolerant, as well as allergic to milk, which may be due to the presence of the indigestible protein casein in it. People who cannot consume milk are advised to switch to fermented milk products.
Milk all information
Discussions about the benefits and harms of milk do not subside all the time. Many experts confirm that milk is a very useful product, and harm is done to the body only in cases related to physiological characteristics of the individual.
Rational use of milk can protect the body from many diseases. Research institutes conduct numerous studies of milk, which reveal more and more new, useful properties of this miracle product.
For example, milk is not considered a drink, but a food. Milk as a nutritious product and remedy has been used since antiquity , healers used milk to treat various types of diseases The most popular type of milk in the world is cow 's milk .
It is about him that we will tell.
Milk composition:
Milk varies in composition depending on many factors (animal breed, diet, health status, etc.), but in general, the composition of milk can be described as follows. Milk is made up of approximately 87% water and 13% matter, which consists of milk fat, protein, milk sugar and minerals.
Milk contains vitamins A, D, and group B (B1, B2, B12), macro- and microelements such as calcium, potassium, phosphorus, magnesium, sodium, iron, fluorine, iodine, etc. A distinctive feature of milk is that the nutrients contained in it are perfectly absorbed by the human body.
The calorie content of milk, depending on many factors, can range from 30 to 80 kcal per 100 grams of product. Milk strengthens the immune system and has a positive effect on many human organs. It is a good remedy for fighting colds and protecting against other diseases.
Scientific research data shows that regular consumption of milk reduces the risk of cardiovascular diseases by 15-20%. It helps to reduce pressure, reduces swelling, milk reduces the likelihood of oncological diseases - various types of cancer. It also has a beneficial effect on the work of the gastrointestinal tract, reduces acidity, copes with heartburn, a healer for gastritis and peptic ulcer.
Useful properties and contraindications– MILK
For better assimilation , it is recommended to drink milk slowly , in small sips . Milk reduces the not always beneficial effect on the body of salty or sour foods. Reduces the risk of developing diabetes.
Milk is necessary for children, as it provides the body with almost all useful substances necessary for the growth and development of the child's body, and, of course, is the main source of calcium for the skeletal system.
Milk has a calming effect on the nervous system, helps to cope with insomnia. A cup of warm milk with a spoonful of honey dissolved in it, consumed an hour before bedtime, is a popular folk remedy for insomnia.
milk is good preventive a remedy for osteoporosis, an important product in the diet of people, as an assistant to people who want to lose weight, experts recommend to many, milk in their diet.
Having consumed milk, the feeling of hunger will go away. Calcium in the composition of milk, significantly reduces the amount of fat in the body, as well (CLG) conjugated linoleic acids contained in its composition and dairy products reduce the formation of new fat deposits.
Contraindications and the harm of milk:
Possessing such wonderful beneficial properties, milk, unfortunately, can be contraindicated and harmful. It is not recommended to consume milk for people with a deficiency of the lactose enzyme, due to the fact that it leads to an upset of the gastrointestinal tract. That's not all, milk can cause allergies.
Contraindicated milk for people prone to deposition of calcium salts in the vessels, as well as the formation of phosphate stones in the kidneys. In addition, in our time, cows, purpose which is in the industrial production of giving milk, all kinds of additives are added to the feed, which include (including hormones), which often remain in milk and can cause irreparable harm to the human body.
If you follow simple rules: drinking milk will bring maximum benefit; Milk is best drunk on an empty stomach 30-90 minutes before meals, in small sips. It is better to combine milk with berries , fruits , honey and nuts , to make milk puddings , mousses and other dishes , to consume them as a snack .
Milk porridge with various cereals will also benefit the body. It is not advisable to immediately drink milk with food. Nutritionists advise to refrain from combining milk with plums, fresh vegetables, smoked and salted fish, sausages. It is also not always useful to use sweet pastries with milk.
Milk benefits, harm, calories
calories different products with milk
- Milk - 50-58 kilocalories
- Coffee with milk - 58-64 kilocalories
- Oatmeal with milk - 102-107 kilocalories
- Wheat porridge with milk - 346 kilocalories
- Rice porridge with milk - 97 kilocalories
- Semolina porridge with milk - 98 kilocalories
The benefits of milk
What are the benefits of milk? Studies show that milk contains more than a hundred valuable components, balanced and fatty amino acids, minerals, including calcium.
Milk is an obvious benefit!
Enough 0.5 liters of this product to replenish the daily requirement of calcium in the human body.
The benefits of milk as a separate product are known to everyone, and the benefits of tea with milk are not known to many. Black tea, of course, can increase blood pressure, but at the same time, it increases protection against heart attack. It is able to strengthen bones and cheer up. Tea and milk are benefits that have been proven by time and numerous studies. Milk enhances the effect of tea rich in antioxidants.
The benefits and harms of milk:
For some, milk is good, but for others it can be harmful. People with osteoporosis, colds, hypertension, heartburn, beriberi, athletes, children under 6 years of age, with insomnia, milk should be consumed 1 cup twice a day.
Harm of milk
Milk by itself is not harmful. But for some diseases it is not suitable. Such ailments include: lactose deficiency, allergy to milk antigen, the presence of phosphate stones in the kidneys.
After the age of 55-60 years, the benefits and harms of drinking milk are not fully understood. However, it still needs to be limited. daily intake product up to 300 grams.
Milk cannot harm the body if it is not consumed in its pure form, but boiled porridge on it. It is better to dilute it with water 1:1.
The product should be consumed gradually, slowly, in small sips. This kind of food will gastric juice it is better to process the milk and get all the nutrients from it.
If the child does not like milk, but he needs it, then you can make cottage cheese or fruit yogurt from it. Children should drink approximately 250-300 grams of milk per day without fail. How younger child, the more dairy products he needs. For getting enough calcium dairy products in the diet are necessary, but within reasonable limits.
If milk or any dairy products are not well tolerated, you can get calcium from vegetables and fruits.
(vit. A)
Human milk is ideal for feeding babies. It is believed that children who have grown up on mother's milk are distinguished by good immunity and general health.
The composition of human milk during lactation varies greatly depending on the diet of the mother, her individual features and even time of day. The total amount of proteins in human milk is 0.9÷2.0%, which is 2-3 times lower than in cow's milk, and casein contains about 40% and whey proteins - 60%. The size of casein micelles is 42 nm.
Human milk contains more lactose - 6÷7% and about 1% of other more complex oligosaccharides that stimulate the development in the intestine baby bifidobacteria. It contains more active hydrolytic enzymes - lipase, amylase, protease, but does not contain xanthiooxidase and is characterized by less active peroxidase and alkaline phosphatase. The main factors in the immunological protection of human milk are the enzymes lysozyme and lactoferrin.
Compound
- Dry matter - 11.9%
- Fat - 3.9%
- Protein - 1.0% (including casein - 0.4%)
- Lactose - 6.8%
- Minerals - 0.2%
Properties
Human milk has the following physical, chemical and technological properties:
- acidity = 3÷6°T, pH = 6.8÷4.7
- density = 1026÷1036 kg/m³
- heat resistance is high (more than 50 minutes at 130 °C), which is explained by low content ionized calcium.
Methods for adapting milk formulas from cow's milk to the composition of human milk are reduced to a decrease in the amount of proteins, balancing essential acids, polyunsaturated fatty acids, minerals(Ca, P, Na), vitamins, protective substances, increased lactose.
Cow's milk
| Whole cow's milk Nutritional value per 100 g of product |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Energy value 60 kcal 250 kJ | ||||||||||||||||||||||||||||||||||||||||
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| 100 ml correspond to 103 g Source: USDA Nutrient database |
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Cow's milk - mother's milk cows - produced in large quantities and is the most traded type of animal milk.
Average chemical composition
- Water - 87,5 %
- Dry matter - 12,5 %
- Milk fat - 3.5%
- Dry skimmed milk residue - 9.0%:
- Proteins - 3.2%
- Casein - 2.6%
- Whey proteins - 0.6%
- Milk sugar lactose - 4.7÷4.9%
- Minerals - 0.8%
- Non-protein nitrogenous compounds - 0.02÷0.08%
- Vitamins, pigments, enzymes, hormones - trace amounts
- Proteins - 3.2%
- gases- 5÷7 cm³ per 100 cm³ of milk
- Carbon dioxide - 50÷70%
- Nitrogen - 20÷30%
- Oxygen - 5÷10%
- Ammonia - traces
Dry milk residue - residue after drying a sample of milk to constant weight at t=102÷105°C.
Dry skimmed milk residue - an indicator of the naturalness of milk. If it is less than 8%, then it is considered that the milk is diluted with water.
Milk normalization - bringing the properties of milk, such as fat content, dry matter content, carbohydrates, vitamins, minerals, to standard or relevant specifications by mixing it with milk having other properties, using a dispenser or separation.
Milk has a liquid consistency not because of the large amount of water, but because all substances are dissolved in each other.
Milk minerals
Study mineral composition milk ash using polarography, ionometry, atomic absorption spectrometry and others modern methods, showed the presence of more than 50 elements in it. They are subdivided into macro- And trace elements .
macronutrients
The main minerals in milk are calcium, magnesium, potassium, sodium, phosphorus, chlorine and sulfur, as well as salts - phosphates, citrates and chlorides.
Calcium is the most important macronutrient in milk. It is contained in an easily digestible form and is well balanced with phosphorus. The calcium content in cow's milk ranges from 100 to 140 mg%. Its amount depends on the diet, animal breed, lactation stage and time of year. In summer, the Ca content is lower than in winter.
Ca is present in milk in three forms:
- In the form of free or ionized calcium - 10% of total calcium (8.5÷11.5 mg%)
- In the form of calcium phosphates and citrates - about 68%
- Calcium, strongly associated with casein - about 22%
It has not yet been clarified in what form phosphates and citrates of Ca are found in milk. These can be Ca phosphate, Ca hydrophosphate, Ca dihydroxophosphate, and more complex compounds. However, it is known that most of these salts are in a colloidal state and a small part (20-30%) is in the form of true solutions.
Phosphorus. The content of P ranges from 74 to 130 mg%. It changes little during the year, only slightly decreases in the spring, and depends more on the feeding rations, the breed of the animal and the stage of lactation. P is found in milk in the mineral and organic forms. Inorganic compounds are represented by phosphates of calcium and other metals, their content is about 45÷100 mg%. organic compounds- this is phosphorus in the composition of casein, phospholipids, phosphoric esters of carbohydrates, a number of enzymes, nucleic acids.
Magnesium. The amount of magnesium in milk is insignificant and amounts to 12÷14 mg%. Mg is a necessary component of the animal body - it plays an important role in the development of the newborn's immunity, increases its resistance to intestinal diseases, improves their growth and development, and is also necessary for normal life microflora of the stomach of the rumen, has a positive effect on the productivity of adult animals. Mg is probably found in milk in the same chemical compounds as Ca. The composition of Mg salts is similar to the composition of Ca salts, but the proportion of salts in true solution accounts for 65÷75% Mg.
Potassium and sodium. The content of K in milk ranges from 135 to 170 mg%, Na - from 30 to 77 mg%. Their number depends on physiological composition animals and slightly changes during the year - by the end of the year, the content of sodium increases and potassium decreases.
Salts of potassium and sodium are contained in milk in the ion-molecular state in the form of well-dissociated chlorides, phosphates and nitrates. They have great physiological significance. Sodium and potassium chlorides provide a certain amount of osmotic pressure of blood and milk, which is necessary for normal processes vital activity. Their phosphates and carbonates are part of the buffer systems of milk, maintaining the constancy of the concentration of hydrogen ions within narrow limits. In addition, phosphates and citrates of potassium and sodium create conditions in milk for the dissolution of poorly soluble in clean water calcium (and magnesium) salts. Thus, they provide salt balance , that is, a certain ratio between calcium ions and anions of phosphorus and citric acid facilitating dissolution. It determines the amount of ionized calcium, which in turn affects the dispersion of casein micelles and their thermal stability.
trace elements
Pollutants
- Toxic elements - lead (not more than 0.1 mg/kg), arsenic (not more than 0.05 mg/kg), cadmium (0.03 mg/kg), mercury (0.005 mg/kg)
- Mycotoxins - aflatoxin M1
- Antibiotics - levomycetin, tetracycline group, streptomycin, penicillin
- inhibitory substances (detergents and disinfectants, antibiotics, soda)
- Pesticides
- Radionuclides - cesium-137, strontium-90
- Hormones - estrogen and similar. IN in large numbers found only in fresh milk, therefore frequent use fresh milk in large quantities can lead to earlier puberty in girls and delayed puberty in boys. After appropriate preparation for implementation, the amount of hormones is reduced to a very low level.
- bacteria
Consumption rates
lactation period
lactation period is the process of formation and secretion of milk from the mammary gland. On average, in cows, it lasts 300 days. It distinguishes 3 stages:
- Colostrum- about 7÷10 days after calving
- The period of obtaining normal milk- 280 days
- The period of obtaining old milk- 7÷14 days before the end of lactation
Colostrum and old-fashioned milk are considered abnormal milk, since a sharp change physiological state animal at the beginning and at the end of the stage of lactation is accompanied by the formation of a secret, composition, physico-chemical. organoleptic and technological properties of which differ significantly from those of normal milk.
| Index | Milk | Colostrum | old milk |
|---|---|---|---|
| Mass fraction of solids | 12,5 % | 25÷30% | 16÷17% |
| Mass fraction of fat | 3,5 % | 5,4 % | 6,7 % |
| Mass fraction of protein | 3,2 % | 15.2% (due to whey proteins) | 5,3 % |
| Mass fraction of lactose | 4,8 % | ↓ 3,3 % | ↓ 3,7 % |
| Min. substances (salts) | 0,8 % | 1,2 % | 0,8 % |
| vitamins | microquantities | ||
| Enzymes | microquantities | lipase | lipase |
| Organoleptic indicators | Color - light yellow or white, Taste - clean, slightly sweet, characteristic of milk | Color - yellow-brown, Taste - bitter, salty, thick consistency. | Color - yellow, Taste - bitter, thick consistency |
| Viscosity | 0.0018 Pa s | 0.025 Pa s | |
| Titratable acidity | 15.99÷20.99°T | 53°T | 14÷16°T |
Chemical properties of milk
- Acidity
- buffering
Acidity- an indicator of the freshness of milk, one of the main criteria for assessing its quality. Determined in milk titrated And active acidity.
Active acidity is determined by the concentration of free hydrogen ions and is expressed pH indicator- the negative logarithm of the concentration of free hydrogen ions in solution, expressed in units of pH.
in fresh milk pH = 6.68, that is, milk has a slightly acidic environment. Active acidity is determined by the potentiometric method on a pH meter.
Milk has a slightly acidic environment, as it contains salts (phosphate and citrate), proteins and carbon dioxide.
Titratable acidity is measured in degrees Turner (°T). In accordance with GOST 3624, titratable acidity shows the number of cubic centimeters of decinormal (0.1 N) alkali solution used to neutralize 100 cm³ of milk or 100 g of the product with a double volume of distilled water in the presence of the phenolphthalein indicator. The end of the titration is the appearance of a faint pink color that does not disappear within 1 minute. Titratable acidity of freshly milked milk = 16÷18°T, acceptable value for normal milk 15.99÷20.99°T .
IN Western countries other units of titratable acidity are used:
- degrees Soxklet-Henkel (°SH) - Germany, Czech Republic, Poland, Slovakia. When determining this acidity, an alkali of 0.25N is used.
- degrees Dornik (°D) - Holland, use alkali 0.09N.
- in percent lactic acid (% lactic acid) - USA, Cuba.
1°SH = 2.25°D = 2.5°T = 0.0225% lactic acid
buffering Buffer systems have the ability to maintain a constant pH of the medium when acids and alkalis are added. They consist of weak acid and its salt formed by a strong base, or from a mixture of two acid salts of a weak acid. The higher the content of buffer properties in milk, the more acid or alkali is required to change its pH. The amount of acid that must be added to 100 cm³ of milk in order to change its pH by one is called buffer capacity milk.
Redox potential is the ability of milk constituents to gain or lose electrons. Milk contains chemical compounds, able to easily oxidize and recover: vitamin C, vitamin E, vitamin B, the amino acid cysteine, oxygen, enzymes. The redox potential of milk is designated E and is equal to 0.25 ÷ 0.35 V. E is determined by the potentiometric method. Factors affecting the change in E:
- Heating milk reduces E
- Presence of metals sharply increases E
- Presence of microorganisms raises E
The redox potential of milk is indirect method determination of bacterial contamination of milk.
Bactericidal properties of milk
Milk after milking contains microorganisms, the number of which within 2 hours not only does not increase, but also decreases. The ability of milk to suppress the action of microorganisms is called bactericidal properties, and the period of time during which bactericidal properties appear in milk is called bactericidal phase .
The bactericidal properties of milk are due to the presence of enzymes (lysozyme, peroxidase), immunoglobulins, and leukocytes in it.
The bactericidal phase depends on:
- bacterial contamination, which depends on compliance with sanitary and hygienic conditions
- milk temperature (the higher, the shorter b. phase)
If the milk after milking is immediately cleaned and cooled to 4 °C, then the duration of the bactericidal phase will be 24 hours, if to 0 °C - up to 48 hours.
Physical properties of milk
- Density
- Viscosity
- Surface tension
- Osmotic pressure and freezing t
- Electrical conductivity
Density- mass of milk at t=20 °C, enclosed in a unit volume. Density is one of key indicators naturalness of milk. It is measured in g / cm³, kg / m³ and in degrees Hydrometer (°A) - a conventional unit that corresponds to hundredths and thousandths of density expressed in g / cm³ and kg / m³.
The density of natural milk should not be lower than 1.027g/cm³=1027kg/m³=27°A. The density of raw milk should not be less than 28°A, for varietal milk at least 27°A. If the density is below 27°A, then it can be suspected that the milk is diluted with water: adding 10% water to milk reduces the density by 3°A.
The density of milk is a function of its composition, that is, it depends on the fat content. Density skimmed milk higher than average, cream density lower than average density milk. The main method for determining density is hydrometric.
Viscosity- the property of a fluid to resist the movement of one part relative to another. Viscosity is measured in Pa s, on average at t = 20 ° C, the viscosity is 0.0018 Pa s. Viscosity depends on the mass fraction of solids, and greatest influence provide proteins, fats, as well as their state of aggregation.
The main factors affecting the viscosity of milk:
- Mass fraction of fat and degree of its dispersion : the more fat and smaller sizes fat globules, the higher the viscosity reading. The viscosity of homogenized milk is higher than that of non-homogenized milk, since the total surface of the fat phase increases.
- Mass fraction of solids in milk: the more, the greater the viscosity.
- Temperature treatment: an increase in milk t to 55 ° C leads to a decrease in viscosity due to more uniform distribution constituent substances of milk and melting of refractory triglycerides that are part of milk fat. A further increase in t leads to an increase in viscosity, since whey proteins are denatured and precipitated on casein micelles.
- Aggregate state of casein: it can directionally change during the technological processing of milk in the process of preparing some fermented milk products (cottage cheese, kefir), while the viscosity increases.
Viscosity is determined on the Ostwald, Geppler and rotational viscometers.
Surface tension is expressed by the force acting per unit length of the interface between two phases air - milk. Surface tension is measured in N/m and is 0.0727 N/m for water and 0.05 N/m for milk. The lower surface tension of milk is due to the presence of surface active substances(surfactant) in the form of milk plasma proteins, shells of fat globules, phospholipids and fatty acids.
Surface tension depends on:
- t environment
- chemical composition of milk
- processing modes
- duration of milk storage
- oxygen content
- aggregate state of proteins and fat
- lipase enzyme activity
In direct proportion to the surface tension is the foaming of milk.
Osmosis- one-way diffusion of the solvent into the solution. The force that causes osmosis, per unit surface of a semipermeable membrane - osmotic pressure. Osmotic pressure of milk normal composition- relatively constant value = 0.66 MPa. It is due to the content in milk mineral salts and lactose. The higher the osmotic pressure, the less likely the development of microorganisms in dairy products. This principle is used in the technology of canned food, as well as in production where syrup (sugar) is used.
Osmotic pressure is calculated from freezing t milk, since the freezing t also depends on the mass fraction of lactose and minerals. freezing t is a constant value, on average it is - 0.555°C(according to GOST 52054 not higher than - 0.520 ° C). Dilution of milk with water leads to an increase in freezing t. According to its size, the naturalness of milk is judged. freezing t is determined by the cryoscopic method.
Electrical conductivity milk - the reciprocal of electrical resistance. It is characterized by the ability of the solution to conduct electricity, the electrical conductivity is measured by Siemens / m. Milk is a poor conductor of electricity, but electrical conductivity can increase in mastitic milk by changing the composition of minerals. Electrical conductivity is due to the presence of hydrogen, potassium, sodium, calcium, magnesium and chlorine ions in milk. For milk = 0.46 Siemens/m.
Organoleptic properties of milk
Fresh raw milk is characterized by certain organoleptic or sensory characteristics: appearance, texture, color, taste and smell. In accordance with GOST 13264-88, the purchased milk must be a homogeneous liquid without sediment and flakes, from white to slightly creamy in color, without extraneous, unusual tastes and odors.
The white color and opacity of milk cause light-scattering colloidal particles of proteins and fat globules, a creamy shade - carotene dissolved in fat, a pleasant, sweetish-salty taste - lactose, chlorides, fatty acid as well as fat and protein. Fat gives milk some tenderness, lactose - sweetness, chlorides - saltiness, proteins and some salts - fullness of taste.
To the number aromatic And flavor substances raw milk can be attributed a small amount of dimethyl sulfide (<0,01 мг%) и метилсульфида (<0,001 мг%), ацетона (<2 мг%), диацетила (<0,1 мг%),свободных жирных кислот(до 10 мг%), в том числе летучих жирных кислот(до 5 мг%), а также незначительное количество ацетальдегида и других монокарбонильных соединений, карбоновых кислот (пировиноградной и молочной), аминосоединений (свободных аминокислот, пептидов, аминов, аммиака).
An increase in the content of chlorides in milk, the above and some other volatile substances, as a rule, leads to a change in the normal taste and smell of milk and the appearance of vices. The causes and timing of their occurrence are varied. Thus, a number of taste and odor defects can appear in milk before milking. These include defects caused by a change in the chemical composition of milk in violation of physiological processes in the animal's body and the entry into the mammary gland with blood of feed substances with a specific taste and smell. For example, colostrum, old milk and milk obtained from animals with mastitis, ketosis and other diseases have pronounced flavors (bitter, salty).
Other defects in taste and smell may appear in milk after milking - in case of violation of the rules for storage, transportation and primary processing of milk. Rancid, oxidized, soapy and other flavors and odors in milk are caused by lipolysis and fat oxidation. A variety of defects are caused by the adsorption of odors from poorly washed containers, unventilated rooms, lubricating oils, gasoline, etc., as well as contamination of milk with detergents and disinfectants, drugs, and pesticides.
Thus, the taste and smell of raw milk is influenced by numerous factors - the state of health, the breed and the conditions in which animals are kept. feeding ration, stage of lactation, duration and conditions of milk storage, modes of primary processing.
Thermal and vacuum processing of milk and dairy products
Purpose and types of heat treatment. Freshly milked milk has an animal body temperature of about 37°C, which then drops to room temperature, i.e. around 20-25°C. This temperature range is optimal for the development of microorganisms found in raw milk. To maintain the quality of milk, it is necessary to prevent the growth of microorganisms. This can be achieved by heat treatment of milk, in which, at elevated temperatures, the number of microorganisms decreases or their complete destruction occurs (thermization, pasteurization, sterilization), or by lowering the temperature (cooling and freezing). The purpose of heat treatment is to exclude the transmission of infectious diseases through milk and to increase the stability of milk during storage. To enhance the effect in the production of dairy products, the heating of milk raw materials to 100 ° C or higher is combined, followed by immediate cooling to the temperatures required by the standard. The effectiveness of heat treatment depends on the resistance of microorganisms, the stability of its components and the intensity of heat treatment. The intensity of heat treatment depends on the temperature used, the duration of its exposure and the movement of the product during processing.
1. Cooling of raw milk and dairy products. In order to inhibit the development of microorganisms. enzymatic and physico-chemical processes during cooling of raw milk and dairy products, the temperature is lowered to 2-10°C and stored at this temperature until processing. Depending on the final cooling temperature, physical and chemical processes can occur in the products to a greater or lesser extent. due to the action of enzymes and microbiological processes. Lowering the temperature leads to the suppression of the vital activity of microorganisms. The effect of exposure to low temperatures on a microbial cell is based on the violation of the complex relationship of metabolic reactions and damage to the mechanism of transfer of soluble substances through the cell membrane. Along with this, there is a change in the qualitative composition of the microflora. Some groups of microorganisms (psychrophiles) are able to multiply rapidly enough at a temperature of 0-5°C. Thus, the cooling of products to low temperatures does not exclude the possibility of its microbiological spoilage, since the causative agents of spoilage of protein-containing products are mainly putrefactive bacteria. When heat is removed, thermal molecular motion slows down and the state of milk components changes, first of all, casein has the predominant number of hydrophobic bonds. At a temperature of about 60°C, the strength of hydrophobic bonds is the highest. As the temperature decreases, the strength of hydrophobic bonds weakens, and agglomerates break up into smaller formations. Disaggregation is reversible, but only partially, and the reverse process proceeds at a slower rate. Therefore, after storing milk for a long time at a temperature of 2-6 ° C, its ability to coagulate with rennet noticeably deteriorates. The resulting clot is characterized by the ability to syneresis and lower strength. The instability of hydrophone bonds leads to an increase in the activity of enzymes. primarily xanthine oxidase and catalase associated with casein and the protein components of fat globules in the shell. Xanthine oxidase catalyses the oxidation of many aldehydes to acids, while catalase catalyses the oxidation of unsaturated fatty acids and alcohols by peroxides. When milk raw materials are cooled, partial hardening and crystallization of milk fat in fat globules occurs, which leads to a weakening of bonds in the shells, since the glyceride layer loses its elasticity and becomes more susceptible to mechanical stress. Cooling and storage of chilled raw milk leads to the destruction of vitamins. For example, vitamin C is destroyed by 18% when storing chilled milk for 2 days and by 67% when storing chilled milk for 3 days. When milk is cooled, the composition of the microflora of raw milk changes - the growth of mesophilic and thermophilic microflora slows down and psychrophilic bacteria begin to predominate, developing in milk from 5 to 15 ° C.
2. Freezing of raw milk and dairy products. During freezing, more noticeable physicochemical and biochemical changes occur than during cooling, and their depth depends on the rate of freezing and the storage temperature of frozen products. The changes are due to the processes of water crystallization, the redistribution of moisture between the structural formations of milk components, and the increase in the concentration of substances dissolved in the liquid phase. The moisture contained in milk determines the consistency and structure of the product, determining its stability during storage. Bound moisture has different properties than free moisture. It freezes at lower temperatures, has a lower dissolution capacity, lower heat capacity, and increased density. The amount of bound moisture, in addition to its physicochemical properties, is determined by its fineness. As the dispersion of the product increases, the amount of bound moisture increases. During slow freezing (-10°C) with the formation of large crystals outside the cells, the initial ratio of the volumes of the intercellular and intracellular space changes due to the redistribution of moisture and the phase transition of water. Rapid freezing (-22°C) prevents significant diffusive redistribution of moisture and dissolved substances and promotes the formation of small, evenly distributed ice crystals. The smallest crystals are formed in the surface layers of the product. When water is frozen, crystals of various shapes are formed, having sharp peaks and edges, as a result of which they can adversely affect coarsely dispersed constituents. The maximum crystal formation occurs at temperatures from -2 to -8°C, therefore, in order to prevent the formation of large ice crystals during freezing, it is necessary to ensure a rapid decrease in temperatures in this range. In addition, in this temperature range, the content of dissolved substances in the non-frozen moisture increases, the rate of some reactions increases, enzymes are released and lipids are oxidized. With slow freezing, about 4% free and 3.5% bound moisture remains unfrozen. In free moisture, the concentration of proteins, mineral salts and lactose is increased. This leads to aggregation and disaggregation of casein micelles and their loss of stability. This is facilitated by the crystallization of lactose during cooling and strong mixing of milk before freezing. With slow freezing, partial or complete denaturation of proteins occurs. Such changes in proteins lead to a decrease in the ability to coagulate under the action of rennet. With slow freezing, the raw milk is stratified. Freezing is accompanied by a decrease in the number and activity of microorganisms without their complete destruction. Due to changes in the state of protein-lipid complexes and mechanical destruction of microbial cells by ice crystals, damage to the membrane structures of the cell is possible. The highest degree of death of microorganisms occurs at temperatures of -10...-12°C. Storage at these temperatures allows you to save products without microbiological spoilage.
3.Pasteurization of raw milk. The main purpose of pasteurization is the destruction of pathogenic toxin-forming microflora and the inactivation of enzymes. As a result, the transmission of infectious diseases through milk and dairy products is excluded and a longer shelf life is ensured. In milk from a sick cow, from the hands of sick personnel, contaminated feed, drinking water, dishes, etc. pathogens such as tuberculosis, brucellosis, plague, anthrax, Escherichia coli, etc. can enter. These diseases can be transmitted to humans through milk. The resistance of various pathogenic microorganisms to temperature is not the same. As a rule, pathogenic microorganisms die at relatively low temperatures. The most resistant to heat of the non-spore-forming microorganisms is the tubercle bacillus. The causative agent of tuberculosis dies at temperatures of 60-65°C within 30 minutes. However, there is evidence that a higher temperature (75 ° C with an exposure of 30 minutes) is required to destroy the tubercle bacillus. This is due to the fact that resistance to temperature conditions, depending on numerous factors, may not be the same for different strains. Therefore, when using milk from cows with suspected tuberculosis, it is necessary to heat it to a temperature of 80 ° C for 30 minutes or boil it. Milk from sick animals must be destroyed. The rest of the non-spore-forming pathogenic microflora dies at lower temperatures than the tubercle bacillus. In this regard, when substantiating the modes of pasteurization of milk, the temperature treatment of tubercle bacillus is taken as the basis. One of the sanitary-indicative microorganisms that can lead to various kinds of toxicosis and intestinal poisoning is the bacteria of the Escherichia coli group (ECG). The presence of these bacteria in milk indicates a violation of the required sanitary and hygienic conditions for milk production. They cannot withstand milk heating up to 60°C for 30 minutes. With the help of pasteurization in milk, only vegetative forms of microflora can be destroyed, since the presence of spores increases the thermal stability of microorganisms by 10-15, and sometimes by 50°C. Heating raw milk to pasteurization temperatures leads to the inactivation of enzymes, the thermal stability of which is as individual as the thermal stability of microorganisms. The temperature regimes of pasteurization adopted in the dairy industry completely inactivate alkaline phosphatase. It is known that after heating milk to 65°C for 30 minutes, phosphatase is not detected in it. Heat treatment of phosphatase is used in the dairy industry to determine the efficiency of milk pasteurization in the production of drinking pasteurized milk. In the production of fermented milk drinks or butter, the effectiveness of pasteurization is determined by a test for xanthine oxidase, which is inactivated at temperatures around 80°C. Proteases are inactivated at temperatures above 75°C, native lipases at 80°C, and bacterial lipases at 90°C. The essence of the thermal destruction of microorganisms and enzymes is the thermal denaturation of the protein components of cells, during which their polypeptide chains unfold with the loss of biological properties. The theoretical foundations of pasteurization are described by the Dahlberg-Cook equation for tubercle bacillus: lnz=α - βt
where z is the temperature exposure time, (s); α,β - coefficients equal to 36.84 and 0.48, respectively; t - pasteurization temperature, (°C). The equation shows the interdependence of temperature and time for the destruction of microorganisms and enzymes. In production, the actual holding time Q during the heat treatment of raw milk should not be less than the theoretical values of z. When Q=z, the pasteurization process is considered to be carried out correctly; at Q
- Long pasteurization t=65°C, z=30 minutes
- Flash Pasteurization t=71-74°C, z=40 s
- Instant Pasteurization t=85°C, z=8-10 s
The efficiency of pasteurization of dairy raw materials in the production of various dairy products depends on the temperature and time of the process. Of great importance is the initial bacterial contamination and mechanical contamination of raw milk. The effectiveness of pasteurization is expressed as the ratio of the number of bacteria destroyed by pasteurization to the number of bacteria contained in the original milk. The pasteurization efficiency should reach 99.5-99.98%. To ensure this value, the sample should contain no more than 3 10 6 CFU per 1 cm³ of the total number of bacteria (mesophilic aerobic and facultative anaerobic microorganisms QMAFAnM), and heat-resistant bacteria should not exceed 3 10 4 per 1 cm³, and bacteria of the intestinal group sticks should not be found in 0.001 cm³ of raw materials. The efficiency of pasteurization according to three indicators after the cooling section of the pasteurization plant is controlled in production at least 1 time per decade. CGBs should not be detected in 10 cm³ of milk, the phosphatase test must be negative, and the total number of mesophilic aerobic and facultative anaerobic microorganisms should not exceed 10 4 in 1 cm³.
4. Sterilization of dairy raw materials. In the dairy industry, raw milk is sterilized according to three principles:
- single stage packed- after pouring milk into the package and hermetically sealing it at a temperature of 115-120°C with a holding time of 15-30 minutes;
- two-stage- preliminary sterilization of milk raw materials in a stream at a temperature of 130-150°C for several seconds, and then secondary sterilization after bottling milk or dairy products and hermetically sealing at a temperature of 115-120°C for 15-20 minutes.
- single-stage with aseptic filling- indirect or direct sterilization of milk raw materials at a temperature of 135-150°C for several seconds, followed by aseptic packaging in sterile containers.
Depending on the characteristics of the production and packaging of the finished product, raw milk is sterilized in a periodic and continuous way. Sterilization in a periodic way is carried out by placing the product in the package in an autoclave and creating a vacuum of 0.08 MPa in it, which corresponds to a temperature of 121°C. At this temperature, the product is kept for 15-30 minutes. Then the temperature is reduced to 20°C. Milk comes to sterilization normalized, homogenized, preheated. Sterilization in a continuous way in the package is carried out in hydrostatic tower sterilizers. The bottled product is fed into the first tower of the sterilizer, where it is heated to (86±1)°C. In the second tower, the bottled product is heated to a temperature of 115-125°C and kept for 20-30 minutes, depending on the volume of the bottle. In the third tower of the sterilizer, the bottles are cooled to a temperature of (65±5)°С, in the fourth - to (40±5)°С. Further cooling takes place in the product storage chamber. The entire processing cycle in the tower sterilizer is approximately 1 hour. Such milk is stored at a temperature of 1-20 ° C for no more than 2 months from the time of production. Sterilization of milk raw materials after filling into a package in a horizontal rotary sterilizer with a valve lock is carried out at a temperature of 132-140°C for 10-12 minutes. The entire processing cycle is 30-35 minutes. For longer storage of milk and dairy products, ultra-high-temperature processing of dairy raw materials in a stream ( UVT-treated), carried out at temperatures of 135-145 ° C with an exposure of 2-4 s with the obligatory carrying out of the technological process after sterilization and packaging in aseptic conditions. UHT treatment of milk ensures the destruction of bacteria and their spores in it, the inactivation of enzymes with minimal changes in taste, color and food texture. The temperature and duration of heating required for this depend on the amount and type of spore-forming microflora in the feedstock. Usually the presence of a large number of spore-forming microflora is associated with an increased total bacterial contamination of milk. When selecting milk for UHT treatment, this fact should be taken into account and raw materials with a total amount of no more than 3·10 5 KOE per 1 cm³ should be used. UHT treatment of milk raw materials is carried out in a stream with aseptic filling using two heating methods:
- direct (steam-contact) heating by injection (injection) of steam into milk or by supplying milk to a steam medium;
- indirect (indirect) heating of milk through a heat transfer surface.
Direct heating of raw milk is effective if it is necessary to immediately heat it up to the sterilization temperature. Milk is instantly heated to a temperature of 140-145°C and enters the holder for 1-3s. Disadvantages of the method: the product comes into direct contact with the heating medium. Milk raw materials must have high thermal stability, and the steam must be subjected to special cleaning so as not to be a source of contamination of sterilized milk. In addition, after steam sterilization, raw milk has increased humidity due to the ingress of condensate into it. The condensate is removed from the milk into a vacuum evaporator, where sterilized milk enters. A vacuum of 0.04 MPa is maintained in the vacuum chamber, at which milk boils at a temperature of about 80°C. The condensate that has got into the milk in the sterilization chamber is removed together with the steam from the milk during boiling. With the indirect method, the heating of milk raw materials is carried out from the heating medium through the heat transfer surface in heat exchange installations. In the dairy industry, tubular and plate heat exchangers are the most common.
Usage
Goat milk is used to treat gastrointestinal diseases, tuberculosis, excretion of heavy metal salts from the body, and for baby food. Some fermented milk products are produced from it - feta cheese and pickled cheeses.
Milk has a high biological value. Its proteins and fats are well absorbed. Milk fat has a low melting point - 21÷23°C, contains less low molecular weight, but more saturated fatty acids compared to cow's milk fat. The amount of polyunsaturated fatty acids in it is almost 10 times higher than in cow's. Proteins have a well-balanced amino acid composition. Mare's milk significantly exceeds cow's milk in the content of ascorbic acid, its amount can reach 13 mg/m³ or more. however, it contains less riboflavin in the blood, and in response to this, calcium is released from the bone to balance the composition of the blood. As a result, the bones become less strong and healthy.According to some studies, cow's milk can cause some forms of cancer, cardiovascular and other diseases.
On the basis of milk and dairy products, medical and dietary products have been developed, including children's products for sick and premature babies, by removing some of the lactose from the swept ("Entips"), by introducing various additives (milk protein hydrolyzate, taurine, polyunsaturated fatty acids, selenium , iron and lysozyme), lactic acid bacteria (acidophthal bacilli and bifidobacteria).
Milk is an exceptional food prepared by nature itself. This product has everything necessary to ensure the normal functioning of a person from birth to old age. In terms of completeness of the chemical composition, no other natural food can be compared with milk. Milk contains more than 100 different valuable components. Here are the main parts of this unique complex: proteins, fats, milk sugar, mineral salts, vitamins, dozens of enzymes and hormones. Each of the components of milk has an outstanding biological value. And one more feature: many components of milk, nature does not repeat in any other products. First of all, milk proteins contain absolutely essential amino acids. Without these acids, not only human nutrition cannot be considered complete, but in general, human life without them is impossible. Growth amino acids (methionine and lysine) are especially important. Milk proteins are more valuable and digest faster than meat and fish proteins. They consist of caseins, albumins, globulins, which contain a complete set of essential amino acids in the ratios required by the human body. Literally all the elements of the D.I. table are collected in milk. Mendeleev, in comparison with many products that are used to build bones, teeth, blood, and nerve tissues. Calcium in milk is better absorbed than calcium in cereals, bread and vegetables, which makes it especially valuable for a growing body, for pregnant and lactating women, as well as for the elderly. Milk also contains trace elements necessary for the body, such as salts, iron, copper and iodine. At all times of the year, milk contains an extensive complex of vitamins, enzymes, hormones and, of course, immune bodies that are very effective in fighting pathogenic microbes. Milk remains one of the healthiest and most nutritious foods today. Half a liter of milk per day covers an adult's need for 30% protein, 25% fat, 75% calcium and phosphorus, 50% potassium. The first food from birth is milk. Love for him in many people persists until old age. For a newborn, milk is the only food, and nature has generously endowed it with biologically active substances. I.P. Pavlov called milk an amazing food prepared by nature itself. In older people, lack of fluid in the body is the cause of poor health, lethargy, fatigue, headache, etc. Milk can be an additional source of liquid. Milk treats gout, disorders of the nervous system, digestive organs, anemia. It was also used as an antidote. Nutritionists believe that milk and dairy products should make up 1/3 of the daily calorie intake. Diet therapy with the use of milk was scientifically substantiated by Russian doctors of the 19th century G.A. Zakharyin, F.I. Inozemtsev, F.A. Karell. Such a diet reduced appetite. The person tolerated this treatment quite easily, painlessly losing excess fat reserves. The scientifically based daily intake of milk and dairy products is about 1 liter. for an adult and 0.5 l. for a child. - milk Cow's milk obtained from healthy animals and meeting the requirements of the standard and sanitary and veterinary rules. [GOST 17164 71] Subjects of production. whole milk prod. from cows. milk Synonyms milk ...
raw cow's milk- žalias karvių pienas statusas Aprobuotas sritis pienininkystė apibrėžtis Natūralus karvių pienas, kuris nebuvo pašildytas iki aukštesnės kaip 40 °C metodu, be priedų, nepakeistos pirminės … Lithuanian dictionary (lietuvių žodynas)
MILK- MILK. Contents: Physiol. value and consumption of M...... 612 Chem. and physical properties of M............ 615 Bacteria M. and their destruction ........ 622 Falsification of M .................. 629 Production and distribution M........ 630 Dairy… …
MILK- MILK. The great Russian physiologist I. P. Pavlov wrote about milk: “Among the varieties of human food, milk is in an exceptional position, and this is a consistent recognition of both everyday experience and medicine. Everyone and always milk is considered ... ... The Concise Encyclopedia of the Household
VEGETABLE MILK- It is produced from various oil-containing fruits. The starting material for the preparation of vegetable milk and grows, cream are 1) American walnut (Pa ranuss), fruits of Bertholletia excelsa. 2) Beech nuts (Buchenkern), beech fruits ... ... Big Medical Encyclopedia
MILK, milk, pl. no, cf. 1. A white or yellowish liquid secreted by the mammary glands of women and female mammals after childbirth to feed an infant or cub. The mother has lost her milk. Goat milk. Mare's milk. 2. Cow's milk... Explanatory Dictionary of Ushakov
MILK, liquid food secreted by the mammary glands of females of almost all mammals for feeding offspring. The milk of domestic cattle, sheep, goats, horses, camels and reindeer has been used by people for food since ... ... Scientific and technical encyclopedic dictionary
milk- A product of the normal physiological secretion of the mammary glands of a cow, sheep, goat, camel, buffalo, mare, obtained from one or more animals from one or more milkings. Note Depending on the type of animal, milk is called ... ... Technical Translator's Handbook
Milk, as a rule, is the first food of a person from birth, and remains the main one for several months. With mother's milk, the baby receives absolutely all the vitamins, minerals and nutrients that he needs for proper development. Milk is a unique product that a person who has come out of infancy continues to consume.
Among the huge variety of types of this drink, cow's milk is the most popular. However, cases when preference is given to goat, sheep, deer and other types of drink are also not uncommon.
Chemical composition, nutritional value and calorie content of milk
Milk is a product, the mineral composition, the content of vitamins and the ratio of proteins, fats and carbohydrates in which directly depends on what the animal ate, what were the conditions of its maintenance and on some other external factors. So, depending on the feed of the cow, the fat content of the drink changes, and with it the calorie content of milk and its taste. In general, it is generally accepted that 100 g of cow's milk contains:
- 88 g of water;
- 3.2 g proteins;
- 2.35 g fat. Of these, saturated - 1.9 g; monosaturated - 0.8 g; polyunsaturated - 0.2 g;
- 5.2 g of carbohydrates, including disaccharides and lactose;
- 28 micrograms of retinol or vitamin A;
- 0.04 g thiamine or vitamin B1;
- 0.18 mg riboflavin or vitamin B2;
- 0.44 mcg cobalamin or vitamin B12;
- 2 IU vitamin D;
- 113 mg calcium;
- 10 mg magnesium;
- 143 mg potassium.
A small amount of cow's milk also contains sodium, phosphorus, sulfur, chlorine, and trace elements - copper, iodine, iron, selenium, chromium, manganese, cobalt, molybdenum, tin, aluminum, strontium.
The calorie content of milk is also a frequently changing indicator, but in general this value is about 60 Kcal per 100 g.
Useful properties of milk
It is unfortunate, but the benefits of milk are significantly reduced when it is pasteurized and sterilized. However, this is the fee for a product that is free of bacteria and harmful impurities. Nevertheless, modern manufacturers strive to ensure that consumers have a product that is not only safe, but also useful.
So, lactose, which is contained in milk, has a beneficial effect on the functioning of the liver, heart and kidneys. Helps her in this casein protein containing the amino acid methionine.
Calcium, which is so useful for the body at any age, is contained in a natural drink in sufficient quantities in a form that is easily absorbed by the body and is perfectly balanced with phosphorus. In childhood, calcium is necessary for the formation of bones of the skeleton, and in the elderly it helps prevent osteoporosis. Curiously, the calcium content in cow's milk is lower in summer than in winter. Experts say that the absorption of calcium increases when it is taken simultaneously with foods containing vitamin D.
The benefits of milk in the treatment of colds have been appreciated by more than one generation. Warm, with the addition of honey or raspberry jam, as well as badger fat, milk is able to revive the most hopeless patient who has come down with a cold. The fact is that the fight against viral infections requires the participation of immunoglobulins - special elements formed from protein foods. Casein - milk protein - is not only an excellent basis for the formation of immunoglobulins, but is also better absorbed by the body than others.
Getting rid of insomnia and headaches are another useful properties of milk. The high content of tryptophan and phenylalanine acids in this drink has a sedative effect on our body. The recipe is simple: a glass of warm, if possible, fresh milk with the addition of honey should be drunk an hour before bedtime. For headaches, it is recommended to add a raw egg to a bowl with a freshly boiled drink. Such a cocktail, taken throughout the week, can get rid of the most severe headaches.
The benefits of milk for heartburn are known to most women who are expecting a baby. This drink reduces acidity and reduces pain in various diseases of the gastrointestinal tract, including gastritis and ulcers. In order to guarantee to forget about heartburn for a long time, you should drink milk slowly, in small sips.
The use of milk in cosmetology began thousands of years ago, when the famous beauty and conqueror of hearts Cleopatra pampered herself with luxurious milk baths. Nowadays, the global beauty industry offers women creams, lotions, gels based on milk proteins, which are designed to give youth and beauty.
Harmful properties of milk
Unfortunately, milk and products based on it are not useful for everyone. Milk with excessive consumption causes harm quite often.
In most cases, the negative consequences of eating this food product haunt those people who suffer from a lack of the enzyme responsible for the breakdown of lactose. Its absence significantly reduces absorption milk sugar, which causes the drink to ferment in the intestines, and this, in turn, causes diarrhea. This phenomenon cannot be called widespread - it is characteristic of only about 15% of the population of our planet.
In addition, cow's milk is a strong allergen. The occurrence of a rash, itching, bloating, nausea or vomiting when drinking it are signs of an allergy that indicate the need to stop taking this drink. However, other milk-based products - cottage cheese, cheese, kefir, yogurt - are digested, as a rule, much better. Unlike cow's milk, goat's milk causes harm in the form of an allergy extremely rarely.
For the elderly, the harm of milk is no less pronounced than the benefit. On the one hand, the drink replenishes calcium deficiency, on the other hand, it is one of the causes of atherosclerosis.
With a tendency to the deposition of calcium salts in the vessels, milk is also contraindicated.
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