And if you think that nothing has changed in recent decades, it is not. Farmers grow food based on its yield, ability to resist disease, but not on the basis of its richness in useful micro and macro nutrients.

Moreover, the problem of hypovitaminosis is not seasonal, winter-spring, when we eat little fresh fruits and vegetables. In fact, for almost 9 months a year, we eat food from greenhouses, frozen, canned, refined or aged for quite a long time. And the content of vitamins in such products is several times less than that of freshly taken from the garden.

Let's first look at what is the daily requirement of our cells in different periods of life in vitamins. After all, a well-known fact: excessive use of vitamins can lead to consequences that you do not expect, for example, if you overdo it with vitamin C, this can increase blood pressure and reduce blood clotting. They overdid it with - calcium began to be deposited in the kidneys, the walls of blood vessels, in the lungs or heart, osteoporosis appeared. Excessive intake of vitamin A dramatically increases the amount of cholesterol in the blood ...

Daily requirement for vitamins at different ages

Our ancestors spent 4000-5000 kcal per day, to make up for these costs they ate about 5 kg of food. Now we do not produce such energy costs, and, accordingly, we do not need to consume such an amount of food, however, the need for vitamins, moreover, in the same quantities as our ancestors, remained.

Let's look at how much food we need to consume in order to at least get closer to the norms for the consumption of vitamins for our body. Moreover, we will pay attention to those products, the content of vitamins in which is the highest.

Table of vitamin content in everyday foods

What affects the content and quantity of vitamins in foods or who robbed us?

Have you noticed such a state that you want to eat something, I don’t know what myself? You look in the refrigerator, and nothing pleases the eye? Today I want something that I would not have looked at yesterday. You start to absorb food, but still somewhere there is a feeling that this is not something, something is missing?

These are symptoms of a micronutrient deficiency. Moreover, you can eat balanced and right. However, according to scientists, even in summer there is a 30% deficiency of vitamin C in the body, what can we say about winter then?

Who is robbing us, and why do the products do not contain vitamins or contain them in small quantities? I will not talk about depleted soils, about the fact that most fruits and vegetables are unripe (and it is in the last stage of ripening that the fruit accumulates all the vitamins and microelements inherent in it), how they are treated with wax for better preservation, you already know all this.

I will tell you how we “kill” vitamins at home, on the kitchen table. The generally recognized "fighter" with winter colds is blackcurrant jam. They just got sick, and our grandmothers begin to solder us with tea with this jam in the hope that vitamin C, which should be contained in it, will save us from a cold. But no!

How do you prepare canned blackcurrants? Scroll through the berries through a meat grinder? In contact with metal and oxygen, vitamin C is completely destroyed. So blackcurrant jam as a cold remedy is a myth.

If you want to keep the vitamins in currants, take a wooden mortar, pestle, crush half of the berries, put the other half in jars whole and close it under the lid so that there is no room for air. So you can save up to 80% of vitamin C.

Do you use water filters? I think so, because it is gaining more and more popularity. But do you know that, for the most part, filtered water is practically distilled water, dead water, there are no trace elements left in it?

Do you eat fat-free cottage cheese and drink low-fat kefir to lose weight? Of course, you will most likely lose weight, but you are unlikely to be able to absorb calcium from these foods, because it is absorbed from foods that have a fat content of more than 6%.

Many, seeking to give the body vitamins, squeeze the juice. However, chasing usefulness, we often miss the fact that, firstly, juices are an incredible amount of fructose, which is instantly absorbed and dramatically increases blood sugar. What leads to the reaction of a hormone such as insulin, whose task is to put sugar in the blood in order. If sugar is constantly jumping, as a result, it ends up with the fact that the body no longer responds to insulin. And this is the first step to the onset of diabetes ...

If you just eat the same apple, your body will need time to get the juice from the apple. Juice will flow gradually, sugar will flow gradually, and there is no insulin surge.

In addition, in the process of squeezing juice, contact with the metal of the juicer occurs - while vitamin C is instantly destroyed.

Enough information? Not? I'll throw some more.

• If you are used to storing vegetables in the refrigerator for 3 days, they lose vitamin C by 30%.
• If you prefer to store vegetables at room temperature - minus 50% vitamin C.
• We cleaned the potatoes and put them in water so that the starch came out (by the way, it is better to use warm water for this), then such potatoes, after lying in water for several hours, completely lost vitamin C.
• Heat treatment deprives us of at least a quarter, or even 100% of all vitamins.

Nightmare, how to live?..

• Leafy vegetables harvested yesterday have lost up to 50% of their vitamin C.
• In order to give your cells enough vitamin C, you need to drink at least 3-4 liters of apple juice, which is made from very fresh apples.
• And, for example, in order to replenish copper in the body, you need to eat half a kilo of nuts a day (and where do we put calories from nuts, comrades? After all, there are 500 kcal in 100 g of nuts? ..)

But not only with the content of vitamin C in foods such losses occur, with other vitamins the same picture:

• Over the past half century, vitamin A has disappeared from beef; apples, bananas, oranges lost it by 66%, chicken meat contains 70% less than our grandmothers had.
• The greens have become impoverished in terms of calcium by almost half. In kale, only 15% of calcium remains.
• Cilantro, parsley, dill, celery contain a third less magnesium. Only 58.5% of iron remains in these products ... Because of all this, half of the population of the countries of the former Soviet Union have anemia -.

We cannot stock up on vitamins for the future, as they are excreted from the body after 5-6 hours. Therefore, if the content of vitamins in foods is so low, it is necessary to look for other sources of micro and macro elements. But that's a story for another article.

vitamin product food value

The information in the tables on the content of vitamins in food products is taken from the Handbook "Chemical composition of food products", 2nd ed., Vol. 2, M., Agropromizdat, 1987. The average daily requirement of an adult for vitamins is taken in accordance with " Norms of physiological needs for nutrients and energy for various groups of the population of the USSR, approved by the Ministry of Health of the USSR in 1991. Priputina L.S. Food products in human nutrition. Kyiv, 1991, page 112

The volumes (quantities) of food products that provide the daily human need for a particular vitamin are calculated taking into account the loss of vitamins during cooking, in accordance with the coefficients of these losses given in the reference book "Chemical composition of food products", v.3, M., Light and Food Industry, 1984. These data are marked with an asterisk (*).

The growth of baker's yeast (Saccharomyces cerevisiae) is dependent on biotin. Therefore, biotin, as a growth promoter, is added to the nutrient medium used for yeast fermentation. Many of the microorganisms used in modern industrial biotechnology also depend on biotin. Therefore, in this capacity, it is added to the growth medium

In cosmetics, biotin is used as a component of hair care formulations.

The synthesis of ascorbic acid was carried out by Reichstein in 1933, and five years later its industrial production was carried out. Currently, synthetic vitamin C, identical to natural, is produced on an industrial basis from glucose by chemical and biotechnological synthesis.

In the food industry, ascorbic acid is used as a natural antioxidant. This means that the addition of ascorbic acid to food products during processing or before they are packaged helps to preserve the color, smell and nutritional value of the food. This use of ascorbic acid has nothing to do with its vitamin activity. In the process of meat processing, the use of ascorbic acid makes it possible to reduce the amount of added nitrites and the nitrite residue in the finished product. (In the stomach, nitrites are converted into potentially carcinogenic nitrosamines.)

The addition of ascorbic acid to fresh flour improves its baking qualities, thereby saving the 4-8 weeks required for the flour to mature after milling. Skurikhin I.M. How to eat right M., 1985, p. 133

Cholecalciferol is produced industrially by exposing 7-dehydrocholesterol, derived from cholesterol, to ultraviolet light by various methods. Ergocalciferol is produced in a similar manner from ergosterol extracted from yeast. The starting material for the production of calcitriol is the cholesterol derivative pregnenolone.

In many countries, milk and dairy products, margarine and vegetable oils fortified with vitamin D are the main dietary source of vitamin D.

Vitamin E, isolated from natural sources, is obtained by molecular sublimation and in most cases by subsequent methylation and esterification of edible vegetable oil products. Synthetic vitamin E is produced from natural plant material by the condensation of trimethylhydroquinone with isophytol.

Vitamin E in the form of dl-a-tocopherol is widely used as an antioxidant (antioxidant) to stabilize edible oils and fats and fat-containing foods.

Studies have shown that vitamin E in combination with vitamin C reduces the formation of nitrosamines (which have been shown to be carcinogenic in animals) in bacon more effectively than vitamin C alone.

Vitamin E is used topically as an anti-inflammatory agent to moisturize the skin and protect it from damaging UV rays.

Folic acid is produced on a large scale using chemical synthesis. Various processes for its production are known. Most synthetic folic acid is used as an additive in animal feed.

Folic acid is added to a variety of foods, the most important of which are breakfast cereals, drinks, soft drinks, and baby food.

The process involves the use of a monoester as menadiol and an acid catalyst. Purification of the desired product to remove unreacted reactants and by-products occurs either in the quinol step or after oxidation.

With the exception of special foods for newborns, vitamin K is not added to food. Vitamin K is synthesized industrially and used in infant formulas (100 mg/litre) and human medicines.

In most cases, niacin is produced from 3-methylpyridine, although other methods are known. This substance is a derivative of two carbon compounds, acetaldehyde and formaldehyde, or from a mixture of acrolein and ammonia. Nicotinamide is synthesized by oxidation with ammonia and partial hydrolysis of 3-methylpyridine. With further continuation of hydrolysis, nicotinic acid is formed.

Pantothenic acid is chemically synthesized by the condensation reaction of D-pantolactone with beta-alanine. The addition of calcium salts leads to the formation of colorless crystals of calcium pantothenate. Pantothenol is produced as a clear, almost colorless, viscous hygroscopic liquid.

Pantothenate is added to a variety of foods, the most important of which are breakfast cereals, beverages, diet foods, and baby food.

Panthenol is often used as a cosmetic product. As part of skin care products, panthenol helps to keep the skin hydrated and nourishes it, and also stimulates cell growth and tissue repair, in addition, it eliminates inflammation and redness of the skin. As a moisturizer and conditioner in hair care products, it protects and helps repair damage caused by chemical or mechanical stress (combing, shampooing, curling, coloring, etc.) and promotes shine.

Water Soluble Vitamins

Vitamin C - L -ascorbic acid 1 - in food products it is in three forms: in the free state in the form of ascorbic acid and its oxidized form - dehydroascorbic acid, as well as ascorbigen - ascorbic acid, indole-bound to proteins.

Ascorbigen has a greater resistance to oxidizing agents and only 5% vitamin activity compared to ascorbic acid. Although vitamin C is called ascorbic acid, it does not contain both an acid, a free carboxyl group, and ascorbic acid oxidase enzymes and other enzymes, oxidizing agents, when heated in a neutral and alkaline environment, resulting in dehydroascorbic acid.

This easy oxidizability explains the reducing properties of ascorbic acid. By its chemical nature, vitamin C is close to monosaccharides and is synthetically obtained from sorbose sugar.

Vitamin C found mainly in fruits and vegetables. Animal products, with the exception of the liver, are poor in them. The richest in vitamin C are dry rose hips (up to 200 mg ° / 0), green walnuts (up to 3000 mg%), blackcurrant, horseradish and sweet pepper (up to 300 mg%), cauliflower (100 mg ° / o), strawberries, spinach, green onions and citrus fruits (40-70 mg%), radish, tomatoes and apples (20 -40 mg%).

Vitamin C is the least stable of all vitamins. It is destroyed in fresh fruits and vegetables during storage, drying and cooking, during the production of juices and cooking, but it is well preserved during fermentation, freezing, canning in hermetically sealed containers. Vitamin C is used as an antioxidant for food preservation, as well as for making beverages.

In the human body, vitamin C is involved in the synthesis of brain proteins, collagen protein and redox processes occurring in every cell of the body.

Lack of vitamin C, and its daily requirement is 75 - 150 mg, causes general malaise, fatigue in the body. This phenomenon is most often observed in winter, spring, when food contains little vitamin C. The absence of ascorbic acid in the body causes scurvy (scurbut), accompanied by hemorrhages on the skin, tooth loss, etc.

Vitamin B 1 - thiamine (aneurine) - in the products is in the form of hydrochloric acid or hydrobromic thiamine. The most rich in thiamine yeast marvelous dry (5 mg%). In pork it is 0.98 mg%, peas - 0.72, buckwheat, oat and barley groats, soybeans, nuts and beans - 0.5-0.6, wholemeal bread - 0.3, veal - 0.2, beef - 0.1 mg % .

Thiamine is resistant to heating and cooking, is destroyed in an alkaline environment, and is easily oxidized by atmospheric oxygen. Its absence in human food causes beriberi and polyneuritis (inflammation of the nerve trunks), leading to paralysis. Lack of thiamine in the body

Vitamin B 2 - riboflavin (lactoflavin) - by its chemical nature, it belongs to the group of yellow coloring substances - flavins. Its molecule contains a residue of the pentahydric alcohol ribotol, hence its name riboflavin.

The most important sources of riboflavin are yeast (4 mg%), liver and kidneys of a bull (up to 2.5 mg%), eggs (08 mg%), milk 0.2 mg%), cheese, cottage cheese (0.4-0.5 mg%), wholemeal bread (0.3 mg%), meat and fish (0.1-0.3 mg%), buckwheat and oatmeal (up to 0.2 mg%), potatoes and cabbage (0.05 mg%).

Vitamin B2 is stable during drying, heating and cooking, it is destroyed in alkaline solutions and under the influence of ultraviolet rays. With a lack of riboflavin in the body, the process of oxidation of organic substances is disrupted, which manifests itself in weight loss, weakness, inflammation of the mucous membranes of the mouth, eye disease, and nervous system disorders. The daily requirement of the body for vitamin B 2 -2.0-2.5 mg.

Vitamin B 3 - pantothenic acid -is a derivative of alanine. In significant quantities, it is found in brewer's yeast (20 mg%), liver (2 mg%), egg yolk (6 mg%), potatoes, cauliflower (0.4 mg%), etc.

Under the action of high - temperature in an alkaline and acidic environment, vitamin B3 is destroyed. It is involved in fat and carbohydrate metabolism, promotes the growth of the body, the activity of the nervous system and digestive organs. The need for it in the human body is up to 10-15 mg per day.

Vitamin PP - nicotinamide (niacin) Andnicotinic acid - Found in many animal and plant foods. Important sources of vitamin PP are yeast (40 mg%), liver (up to 22 mg%), meat, fish (2-6 mg%), buckwheat (4 mg%), beans (2 mg%), oatmeal and potatoes (1 mg%), whole wheat bread (3 mg%), cabbage (0.4 mg%), eggs (0.2 mg%) , milk (0.1 mg%) and etc.

A lack of nicotinamide in food causes a violation of oxidative processes and a weakening of the body, and a lack of it causes pellagra disease, which manifests itself in skin inflammation, disruption of the gastrointestinal tract and nervous system.

Vitamin B 6 - pyridoxine (adermine) - found in dry yeast (up to 5.5 mg%), liver, meat and fish (up to 1 mg% ), beans and peas (0.7 mg% ), wheat (0.3 mg% ), potatoes, carrots and cabbage (0.2-0.1 mg% ) and etc.

Pyridoxine is resistant to high temperatures, is destroyed in products during frying, smoking and stewing, as well as under the action of light.

It has a positive effect on the human body with radiation sickness, intestinal infections, skin diseases. Lack of it in food disrupts the conversion of amino acids in the body and causes an inflammatory skin lesion (dermatitis). The human body requires pyridoxine 1.5 mg per day.

Vitamin B 9 - folic acid - is found in plant and animal products. The most rich in folic acid are liver, meat, fish, beans, spinach, potatoes, cabbage. It is involved in the processes of transformation of nucleosides. Its absence in the body causes a disorder of the nervous system, anemia.

The daily requirement of the body for folic acid is 0.1-0.5 mg . It is used in the treatment of "radiation diseases" associated with exposure to x-rays and other penetrating rays.

Vitamin B 12 - cyanocobalamin - found in the liver, kidneys, egg yolk, crabs, dairy products and others, is involved in the processes of protein synthesis, fat metabolism, hematopoiesis. Daily dose - 0.005-0.05 mg . Its absence in the body causes pernicious anemia.

Vitamin H - biotin - is a growth stimulator of yeast and other microorganisms. It is believed that biotin is synthesized by microorganisms in the human intestine. Biotin is found in many foods. The richest in them are kidneys, liver, egg yolk, beans, soybeans, nuts, milk. Lack of biotin (daily human requirement 0.010-0.025 mg) causes inflammation of the skin, hair loss.

Fat soluble vitamins

Vitamin A - retinol (axerophthol) - Found in animal products. Plant foods contain provitamin A (an orange-red coloring matter).

Retinol-rich marine fish fats (up to 90 mg%), beef liver (15 mg%), egg yolk (15 mg%), summer butter (12 mg%).

There is a lot of carotene in red pepper (10 mg%), carrots (9 mg%), sorrel (8 mg%), green onions (6 mg%) , tomatoes, apricots (2 mg% ), apples (0.1 mg%).

It is well preserved during cooking, fermentation and heating without air access, but is destroyed during prolonged frying, drying, as well as during hydrogenation and spoilage of fats.

In industry, retinol is obtained from the liver of cod, halibut, sea bass, whales and seals, as well as from essential oils and acetylene (acetylene - isobutylene - citral - vitamin A).

Vitamin D - calciferol - is a group of substances that regulate phosphorus-calcium metabolism in the human body. The most well studied of this group are vitamins D 2 , D 3 , D 4 , which are obtained by irradiation with ultraviolet rays of sterols - ergosterol, dehydrocholesterol and hydroergosterol. Vitamin D 3 is found in fish oil, cow butter, etc.

Vitamin D enters the human body mainly in the form of ergosterol, which is found in many foods. Ergosterol is found in the subcutaneous fat layer of animals and humans, under the influence of ultraviolet rays of sunlight, it turns into vitamin D.

Sources of vitamin D are flounder liver fat (up to 15,000 mg%) and cod (6-37 mg%), beef liver (1.2 mg%), egg yolks (1.0 mg%), milk (0.3 mg% ), meat (0.1 mg%).

Summer milk and butter, as well as summer sock eggs, are richer in vitamin D, since animals and birds are in open pastures and are exposed to sunlight. From plant foods, vitamin D is found in mushrooms. It is well preserved during canning and cooking. In industry, it is obtained from yeast and whale liver.

Avitaminosis D - a disease called rickets - manifests itself in the softening and curvature of the bones as a result of a violation of calcium and phosphorus metabolism. With a lack of vitamin D, the body's resistance to infection decreases, and bone fractures easily occur. The daily dose of vitamin for an adult is 1- 2 mcg, children - 17-20, a patient with rickets - 40-60 mcg.

Vitamin E - tocopherol - is a monohydric alcohol. Vitamin E is rich in vegetable sea buckthorn (168 mg%), soybean, corn, cottonseed (81-101 mg%) and sunflower (42 mg%) oils, flounder and halibut liver (40-55 mg%), lettuce (18.7 mg). %), peas, butter, cheeses (3.5-6.5 mg%), beans, cabbage, cream, green onions (up to 2.5 mg%), carrots (1.2 mg%), etc.

Tocopherols are sensitive to ultraviolet light, resistant to heating up to 200 ° in the presence of oxygen and the action of acids and alkalis. Vitamin E is used as an antioxidant to protect fats from burning.

In the human body, vitamin E prevents the autoxidation of intracellular fat and increases the performance of muscles, including the heart muscle. It is used as a means to slow down aging and increase a person's athletic performance. Daily rate - 10-25 mg .

Vitamin E is essential for animal reproduction processes. The absence of it in the food of animals leads to infertility, growth retardation, damage to the nervous and muscle tissues.

Vitamin K-phylloquinone - represents a group of vitamins from K1 to K7. Vitamin K1 is found in pork liver (8 mg%), spinach, cabbage and nettles (up to 4 mg%), tomatoes (0.8 mg%) , potatoes (0.16 mg%), cod liver oil, etc. Vitamin K2 is formed by microflora in the human intestine and thereby reduces the body's need for vitamin K. Vitamin K promotes the synthesis of prothrombin in the liver.

Its absence in the human and animal body causes delayed blood clotting, hemorrhages in the skin, muscles, and brain. For treatment, vitamin K3 and its water-soluble bisulfite derivative vikasol, which has the same activity as vitamin K1, are used. Daily intake of vitamin K-10-15 mg .

Natural biologically active substances

Important natural biologically active substances, previously referred to as vitamins, are: essential polyunsaturated fatty acids, which are involved in building tissues of the human body; pangamic acid, methylmethionine and others that are intermediate metabolic products; bioflavanonds that do not cause specific vitamin deficiency.

Polyunsaturated essential fatty acids linoleic, linolenic and arachidonic acids were previously called vitamin F. Linolenic and linoleic acids are found in vegetable oils, where they make up 34-66% of all fatty acids, and are found in small amounts in butter and animal fats.

Arachidonic acid is mainly found in fish fats. Arachidonic acid has the highest biological activity. The human body cannot synthesize linoleic and linolenic acids, and the synthesis of arachidonic acid is possible from linolenic acid in the presence of vitamins B 6 and E.

Essential fatty acids are involved in the process of absorption of fats and fat metabolism of the skin. A complete food should contain 0.1% arachidonic acid or 1% linoleic and lipolenic acids.

Pangamic acid (previously called vitamin B15) is found in the liver, yeast, rice seed husks and others, is used in the treatment of liver diseases and atherosclerosis, the daily norm is -2 mg .

Methylmethionine - an activated form of the amino acid methionine (formerly called vitamin U after the first letter of the Latin word ulcus - ulcer, anti-ulcer), found in vegetable juice (especially in white cabbage), milk, green tea, etc. It is an active biological restorer, heals wounds on the mucous membrane of the gastrointestinal tract, has a positive effect on cardiovascular and skin diseases.

Bioflavonoids - a group of compounds derived from flavan, which have the ability to reduce the permeability of blood capillary vessels. Some researchers attributed them to vitamins of the P group. These include d-catechin, flavanoids of citrus fruits, onions, asparagus, grapes and other fruits and vegetables, polyphenols - tannin of grapes, tea, etc.

Bioflavonoids are rich in black currant (1000-2140 mg%), lemon peel (up to 500 mg ° / 0), plums (110-1080 mg%), red pepper (300-450 mg%), grapes, lingonberries, blueberries, cranberries ( 320-600 mg ° / 0), table beets, cabbage, carrots (up to 75 mg%). The daily requirement of the human body for them is 50-100 mg, they enhance the biological effect of vitamin C.

Antivitamins

Substances that inhibit the biological activity of vitamins are called antivitamins. Most of these are compounds that are similar in chemical structure to the corresponding vitamin and displace it from the enzyme system, or it is a foreign protein that firmly binds the vitamin (for example, raw egg white avidin glucoprotein combines with biotin to form an insoluble compound).

The antivitamin of L-ascorbic acid is D-ascorbic acid (in soy), thiamine - pyrithiamin (in raw fish, oysters), pantothenic acid. Antivitamin properties are used in medicine sulfa drugs, quinine, quinine, etc.

Vitamin A. In animal products, this vitamin is found in its active form - retinol. In plants - in the form of provitamin beta-carotene and other carotenoids.

In finished food products, retinol and carotenoids are dissolved in the fat phase. The rate of their oxidation and the loss of vitamin properties depend on the rate of fat oxidation. Factors that accelerate fat oxidation also accelerate the oxidation of vitamin A at the same time. The stability of vitamin A depends on the type of product. High stability is observed in vitamin dissolved in oil, in the composition of whole milk powder, soft drinks, canned juices, margarine. When cooking food in water, 16% of vitamin A is destroyed after 30 minutes, 40% - after 1 hour, 70% - after 2 hours. When frying (temperature 200 C), 40% of the vitamin is destroyed after 5 minutes, 60% - after 10 minutes, 70% - after 15 minutes. During drying and sterilization of fruit and vegetable products, the content of vitamin A is reduced by 15-20% in green products and by 30-35% in red products. Milk exposed to daylight loses up to 10% of vitamin A within 6 hours.

Vitamin B1 (thiamine) is unstable in neutral and alkaline solutions, where metal ions (copper, iron, etc.) affect its stability. Vitamin is sensitive to light, but resistant to atmospheric oxygen. Thiamine is stable in products containing agar, gelatin, dextrin. The addition of grain products (for example, to canned pork meat) also has a stabilizing effect.

When food is frozen, thiamine is destroyed in the presence of the enzyme thiaminase. This is observed in particular in raw fish. The loss of thiamine occurs when washing fruits and vegetables. Sliced ​​and finely ground food products lose from 20 to 70% of vitamin B1 due to this. During storage of food, vitamin loss occurs if substances of a phenolic nature are present.

Vitamin B2 (riboflavin). It is present in food products in free and bound form. In milk, it is in free form, which determines the yellow-green color of whey. Relatively resistant to oxidation and low pH. Easily destroyed in alkaline conditions, sensitive to light.

Vitamin B9 (folic acid). Contained in raw materials and food products in various forms, differing in biological activity and stability. Soaking fish in water for 12 hours causes a 5% loss of the vitamin. Sterilization of canned food in cans at a temperature of 118 C for 30 minutes leads to a decrease in the vitamin content by 10%. Under more stringent temperature-time processing conditions, a complete loss of the vitamin occurs. When cooking under pressure, the loss of vitamin is from 25 to 50%.

Vitamin B6 (pyridoxine). Stable in acidic and alkaline environments. The main losses occur when dissolved in water. When freezing vegetables, the content of pyridoxine decreases by 20-40%, in frozen products of animal origin - by 40-60%, when cooking meat - up to 50%, and when canning it - by 40%.

Vitamin C (ascorbic acid). Easily extracted with water from food raw materials. Easily oxidized by atmospheric oxygen, especially in the presence of copper and iron ions. Rapidly destroyed in the presence of riboflavin. Relatively resistant to radiation. Heat treatment leads to a decrease in the content of vitamin C. The loss depends on the degree of grinding of raw materials and the amount of added water and ranges from 25 to 60%.

To ensure the content of a sufficient amount of vitamins in the diet, it is important to know not only which foods are rich in vitamins, but also how the storage and processing of products affect the preservation of vitamins in them. Various factors (boiling, freezing, drying, etc.) have different effects on different groups of vitamins.

How vitamins are destroyed

The least stable of all vitamins is vitamin C, which begins to break down when heated to 60 °. Access to air, sunlight, increased humidity contribute to the destruction of vitamin C. Vitamin A is more resistant to high temperatures, but is easily oxidized when exposed to air.
Vitamin D withstands prolonged boiling in an acidic environment, and is quickly destroyed in an alkaline environment. B vitamins are relatively little destroyed during cooking. The least stable of them is vitamin B1, which is destroyed by prolonged boiling and an increase in temperature to 120 °. The most resistant to the action of high temperature is vitamin E, which can withstand boiling for any duration.
Long-term storage and drying have a detrimental effect on vitamins A, C, but do not destroy vitamins D, E, B1, B2.
Since vitamin C is the least stable compared to others, the measures that contribute to its preservation, to a certain extent, preserve other vitamins contained in food products.

What foods contain vitamins

Dairy products are among the most widely consumed foods. Fresh cow's milk contains vitamins A, B1, B2, in a smaller amount C, PP and D. The content of vitamins in milk varies depending on the nutrition of the cow. In summer, when cows usually eat fresh green fodder, there are more vitamins in milk. At the end of winter, cow's milk is especially poor in vitamins, in particular vitamin A. Methods of storage and processing of milk affect the content of vitamins in it. So, storing milk in light glassware leads to the destruction of vitamins C and B2. Skimmed milk does not contain vitamin A. Condensed milk retains vitamin A, but vitamin C is absent.
Boiling milk in a container with an open lid significantly reduces the content of vitamins in it. Prolonged and especially repeated boiling destroys vitamin A to a large extent.
Cow's milk can serve as a source of vitamins only in combination with other foods. This should be remembered especially in cases where it is the main type of food (in children of the first months of life with artificial feeding). At the same time, already from the age of 3 months, vitamins introduced into the body of a child with milk are not enough, and in order to avoid the development of hypovitaminosis, it is necessary to give the child (as prescribed by a doctor) fruit and vegetable juice, fish oil.

A good source of B vitamins are lactic acid products (kefir, etc.), obtained from milk as a result of lactic acid fermentation.
Butter contains mainly vitamins A and D, and there are more of them in summer butter than in winter. These vitamins are also found in ghee. Storing oil in a warm room and in an open container leads to rapid deterioration of the oil and rancidity. At the same time, the vitamins contained in it are also destroyed. Margarine is enriched with vitamins artificially.

Meat products (fresh beef, lamb, veal, pork) contain a sufficient amount of vitamins B1, B2, PP, a little vitamin C, very little A and D. For better preservation of vitamins, it is recommended to cook meat in salt water, in which it should be put after boiling water. At the same time, a crust is formed on the surface of the meat due to the coagulation of proteins, which retains nutrients and vitamins in it. The same crust is formed when roasting meat. Long-term preservation of B vitamins in meat is achieved by freezing it at a temperature of - 20 °. Fresh fish meat contains vitamins B1 and B2. The liver and fat of fish (especially cod) are rich in vitamins A and D. When frozen, the vitamins in fish meat are preserved. Frozen fish should be cooked immediately after thawing, as it will spoil quickly after thawing. A fairly large amount of vitamins A and D is found in fish caviar.

Eggs contain vitamins B1, B2, A, D and PP. Most of them are found in the yolk, vitamins B2 and PP are also found in the egg white. Eggs laid in summer are richer in vitamins (especially vitamin D).
A large place in the diet of the population is occupied by grain products and products from them. Grains contain mainly vitamins B1, B2 and PP. The largest amount of vitamins of this group is found in the germ and the shell of the grain, so wholemeal wheat and rye flour, bran is much richer in vitamins than premium flour (30%). Accordingly, bread baked from wholemeal flour contains more vitamins than bread made from premium flour. A significant amount of vitamin B1 is contained in soy flour, which can be added to ordinary flour to enrich the latter with vitamin B. In addition to soy, B vitamins are found in peas and beans. Rice, especially polished, is poor in vitamin B. Semolina, pasta, noodles contain little or no vitamin B1. In buckwheat, oatmeal, this vitamin is present in sufficient quantities.
Vegetables and herbs are widely used food products. Vegetables have been consumed by humans since ancient times. Wise folk Russian proverbs have long been known, which are not devoid of deep meaning: “Onions from seven ailments”, “Whoever eats carrots will have a drop of blood.”

Even Hippocrates used vegetable juices as a dietary remedy. Hippocrates especially recommended cabbage, since at that time it was credited with the ability to protect against many diseases, heal wounds, etc. Cabbage, cucumber, rare juice, etc., are still widely used among the people as a remedy.
The most commonly eaten vegetables include potatoes, cabbage, carrots, tomatoes (tomatoes). Cabbage and tomatoes are rich in vitamin C. It is somewhat less in potatoes, but since potatoes are consumed almost daily and in significant quantities, it is an important source of vitamin C. Carrots contain carotene, vitamin A is formed from oblique in the human body. In green onions, dark green lettuce, parsley, red pepper, tomatoes, spinach, sorrel, radish contain vitamin C and carotene.

The level of vitamins in vegetables and herbs depends on the conditions of their growth, storage methods and cooking. For example, tomatoes grown in shady areas contain less vitamin C than those grown in sunny areas. Based on this, the artificial ripening of tomatoes in the room is recommended to be carried out with maximum access to light, and not in the dark. In autumn, it is enough to eat 250-300 g of young potatoes to satisfy the body's daily need for vitamin C, and in spring, compared to autumn, you need to eat 5-6 times more potatoes.

How best to process vegetables and herbs so that they retain vitamins

For better preservation of vitamins in vegetables and herbs, in particular vitamin C, their proper processing is necessary. Cleaning and cutting of vegetables and herbs should be carried out shortly before the preparation of the corresponding dishes from them. Otherwise, there will be a rapid destruction of vitamin C under the action of substances released from vegetables and herbs - enzymes.
When cooking, vegetables should be put in a boiling liquid (water or broth), and not cold, to reduce the loss of vitamin C. Placed in boiling water, peeled potatoes lose about 20% of vitamin C, and when lowered into cold water - up to 40%. When preparing various soups, vegetables should be cooked only until they are ready and not laid at the same time. So, for example, when cooking borscht, you must first lower the beets into the broth, which must be boiled for 45-60 minutes, and 30 minutes before the end of cooking, put potatoes and roots in the soup. Potatoes boiled with their skins lose less vitamin C than boiled potatoes.
Potatoes boiled with skins retain up to 75% of vitamin C, and during the day its amount remains unchanged. Vitamin C is better preserved when frying potatoes in oil. A lot of vitamin C is lost in the preparation of mashed potatoes, cooking green peas and green beans. The water in which vegetables were boiled is recommended to be used in the preparation of various dishes, since a significant amount of vitamins, especially vitamin C, passes into the broth. Vitamin C is better preserved in soups seasoned with wheat or soy flour. Of great importance for the preservation of vitamin C is the dishes in which food is cooked. In enameled, aluminum dishes, vitamin C is not destroyed. Properly tinned copper and iron utensils also do not destroy vitamin C.

According to the rules established by the Ministry of Health, the dishes must be tinned with tin with a lead content of not more than 1%. If the half-day is violated, the destruction of vitamin C in products is significantly accelerated when they come into contact with copper and iron parts of the dishes.
Cooking vegetables should be carried out with minimal access to air, since the intake of air contributes to the destruction of vitamin C. Therefore, the water in the pan should cover the vegetables, and the pan should be closed with a lid. In frozen vegetables (potatoes, cabbage), vitamin C is almost completely preserved. However, it should be remembered that after thawing their vitamin C is destroyed very quickly, so vegetables should be thawed as soon as possible, immediately before eating. Frozen vegetables cook 2-3 times faster than fresh ones.

What fruits and vegetables are rich in vitamin C

A good source of vitamin C is sauerkraut, provided it is properly fermented and stored. When pickling cabbage, it is best to use doshniks. It should be stored under oppression and at a temperature not higher than 2-3 °. The brine should completely cover the cabbage. Sauerkraut should be light amber, yellow in color, not slimy or sticky, have a pleasant smell and slightly acidic taste, without bitterness. Before eating, it should not be washed for a long time. Cabbage brine, into which part of vitamin C passes, can be added to first courses, vinaigrettes. The tops of radishes, carrots, rutabaga, parsley leaves, dill, containing a lot of vitamin C, can be used in soups. Tops of beets, carrots can be used as a salad. It is useful to add green onions, dill to ready-made dishes before serving them on the table.
It should be noted that vegetables such as spinach, dill, onions, radishes, parsley, celery can also be grown indoors, which is especially important in northern areas. In autumn, dill, onions, radishes ripen well; at the same time of the year, tomatoes are grown that did not have time to ripen in the ground in the summer. During the winter period, you can grow parsley and celery, onions on a feather, as well as beets on the window to get young tops.
A significant amount of vitamin C contains horseradish, which has been known since the 16th century as a remedy for scurvy. When storing grated horseradish in vinegar in a sealed container, the amount of vitamin C in it remains unchanged for almost a month. Fresh cucumbers are poor in vitamin C, and in pickles, as well as in salted green tomatoes, it is completely absent. Important sources of vitamins are fruits and berries. Blackcurrant is very rich in vitamin C. Gooseberries, strawberries, lemons, oranges, tangerines, dogwood, strawberries, blueberries, red currants contain quite a significant amount of this vitamin.
There is little vitamin C in apples; from various varieties of apples, Antonovka and Titovka are richer in vitamin C. There is little vitamin C in cranberries and grapes, slightly more in Arnica.
When storing lemons, oranges, blackcurrants, vitamin C is stored in them for a long time (6 months or more), in apples, the amount of vitamin C decreases during storage. Dried blueberries do not contain vitamin C. In addition to vitamin C, fruits and berries contain other vitamins in smaller quantities. For example, apricots, peaches, bananas contain carotene, and apples contain a small amount of vitamin B.

Of the berry infusions, blackcurrant is the richest in vitamin C. Infusions are prepared as follows:
the collected berries are moved, washed with a stream of boiled cold water, rubbed through a sieve. Puree juice is mixed with one and a half or double the amount of granulated sugar by weight, mixed thoroughly and put on ice for 1 - 1/2 days. Then everything is bottled in clean bottles. The bottles are hermetically sealed at a temperature of 3-4°.
When cooking jam from various berries, vitamin C is destroyed to a large extent.
Ordinary bee honey contains few vitamins, but at present, the food industry produces polysitaminated honey enriched with vitamins A, B1, B2, C, PP, D.
A significant amount of vitamins B and PP is found in fresh mushrooms. When drying, salting and pickling mushrooms, their vitamin content decreases. A large amount of vitamin B is found in nuts. When eating, nuts should be crushed for better digestion.
An important branch of the food industry is the canning industry, which produces a large number of canned meat, fish, fruits and vegetables.
Based on the materials of the popular science brochure Efimov N.I. "Vitamins and their importance for a healthy person"

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