White and brown chicken eggs: which are healthier? Why do chickens lay green yolk eggs?

The color of the eggshell, as well as the shade of the yolk, excites the potential consumer, since in his mind, products that have a darker shell color and a more saturated shade of yellow substance are directly related to more high content valuable items. Is this true and how the color scheme affects the strength and taste characteristics of the product, let's try to figure it out in this article.

Experts note the fallacy of this approach, since more yellow and even orange shades of the scale may not indicate at all an increased nutritional value of eggs, but the use of special chemicals when feeding laying hens. On the other hand, a slightly colored yellow substance of the chicken masonry product may indicate a weakened organism of the individual who produced it, or that poor quality grain was used in the process of feeding it, and there were almost no nutritional supplements.

The answers to these questions are inextricably linked to the factors that affect the color of the eggshell and the saturation of the hue of the yolk. There is a controversial opinion among the population that the brown color of the egg shell indicates the “home keeping” of the laying hen, in contrast to the products of the white shade of the shell, to which they attribute lower nutritional qualities. Despite the fact that the shade of the shell, according to scientifically proven data, is determined by the breed of chicken, habitat and conditions of detention, people stubbornly believe that White color products is a marker of their factory receipt.

In turn, the light shades of the shell and the central part of the egg, associated, in their opinion, with obtaining in an incubator, imply worst conditions content than in subsidiary farms and farms and, as a result, lower nutritional quality of such products. In fact, scientists have not found any correlation between the color of masonry elements and their consumer characteristics. And some scientists even cite the fact that colored eggs are more prone to blood stains in the yolk area to refute the prevailing opinion, which reduces the demand for this type of product.

As known from school course biology, the formation of traits is influenced by a combination of genetic information and external conditions, which manifests itself in a change in the inherent characteristics under the influence of parameters environment.

What determines the color of the shell of a chicken egg?

Experts identify the following factors that affect the shade and color of the shell of a chicken egg:

Important! Experienced breeders call earlobe color, according to their observations, coinciding with the range of eggs laid. In addition, experts say that the color of the shell surrounding the fetus is determined by genetic information and will persist throughout the life of layers.

1. Impact of external conditions can cause pigmentation of the membrane, its change can be caused by the influence stressful situation experienced by the bird 4-5 hours before laying. In this case, the state that has arisen through the nervous system has an effect on the mucous membranes of the oviduct, impeding the entry of porphyrins and limiting the release of pigment from the region of the gland responsible for the formation of the membrane.
2. Some breeders note that the weakening of the shades of masonry color may be associated with the use medicines.

Important! The addition of a preparation containing 5 mg of nicarbazine / day, used in veterinary medicine for the treatment of cocidia, to birds, causes a visible change in the color of the eggs. The use of large doses of this substance can lead to a complete loss of pigmentation of the masonry elements.

1. Lightening of the shell may be associated with d the chicken's long exposure to the sun, as an example, experts cite the weakening of pigmentation observed in the Maran species.
2. Bias colors in the direction of light tones may be due to increase in ambient temperature and drinking water.

Note! When the air temperature rises from 24 to 30 ° C or when water with a temperature above 50 ° C is supplied to the drinkers for chickens, eggs laid by birds with dark color feathers acquire light shades.

Important! The intensity of the color gamut can change under the influence of the birds transferred diseases of an infectious nature and due to damage to the body of the chicken helminths.

1. Partially, the color of the final product can be influenced individual physiological processes in the body of the laying hen. If, as a result of acting factors or conditions of detention, the time of passage of the egg through the oviduct increases, it is highly likely that the shell will have a darker shade at the exit. This fact is due to a longer effect on the shell of porphyrin, an enzyme that determines the color of eggs, when they pass through the intrauterine tract.

Note! This fact can be confirmed by the fact that within the same clutch, the first egg hatched from the oviduct has a darker shade of color than the subsequent ones.

1. A darker shade of color is given to the shell by a coloring matter called protoporphyrin contained in hemoglobin and vitamins.

As for the strength of the shell, it is not the color of the product that determines it, but the age of the laying hen, the feed and the presence of additives in the diet of the hen, the phase of the laying cycle, the season of the year. So, young chickens have eggs with a stronger shell, the hardness of the shell increases in the presence of good nutrition, at the beginning of the masonry cycle, the shell has a greater thickness. On the other hand, a decrease in strength can be affected by vitamin deficiency that occurs with an unbalanced diet and in the spring season.

Video: what is the difference between white and brown chicken eggs

The yellow substance of the egg makes up a little more than 1/3 of the total volume of the egg and can range from a faintly colored yellow to a rich golden and even orange tone.

What determines the color of the yolk in a chicken egg?

Among the factors affecting the color saturation of the yolk of a chicken egg, experts call:

• Consumption of large quantities by laying hens feed that has saturated color , as a result of which the pigments of the carotenoid group contained in them also affect the shade of the emerging yellow substance of the egg. Among the substances with coloring properties that affect the color saturation of the yolk, experts call xanthophyll and lutein.
• It is possible to ensure the delivery of these substances to the body of the chicken, including in its diet grass flour and corn varieties having the appropriate saturated hue. Possessing antioxidant properties, these pigment substances improve the condition musculoskeletal system birds and take part in the synthesis of vitamin A in the body.
• In conditions household properties of carotenoids can perform fat-rich food. So, a brighter shade of yolk in chickens can be obtained by including kitchen waste in their diet containing a large number of fats, adding to food whey and mixed, diluted with herbs.

Note! In the case of the predominance of light varieties of alfalfa and corn in the feed, a weak color gamut is transferred to the yellow substance.

Video: what affects color egg yolk

Scientists say that the shade of the color of the yolk does not affect nutritional value product. According to their data, it is the yellow substance of the egg that has the highest concentration of protein, and this property of the product and its ratio relative to the protein mass is preserved regardless of the saturation of pigmentation. In conclusion, it should be said that scientists have not found a relationship between the color of an egg and its taste characteristics. The taste of the yellow substance of the fruit does not depend on the color of the shell or the color of the yolk, but on nutrition. Experts say that with the same feeding, products produced by layers with colored feathers will have the same taste characteristics.

Video: why chicken eggs different color

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How to know if an egg is fresh and why an egg floats in water; does the chick breathe in the egg; what is the danger of raw eggs; at what temperature does salmonella die; how to cook and store chicken eggs; Can eggs be stored in the freezer? why are there two yolks in an egg, as well as others Interesting Facts about eggs.

1. What does a chicken egg consist of?

The formed egg consists of protein, yolk, shell and membranes. In a chicken egg, 10-12% of the mass is the shell, 56-61% is the protein and 27-32% is the yolk. In the liquid content of an egg without a shell, the protein accounts for approximately 64%, and the yolk - 36%.

2. What is an eggshell made of?

According to studies by Hungarian doctors, it has been proven that the egg shell is 90% calcium carbonate (calcium carbonate). In addition, the shell also contains magnesium (0.55%), phosphorus (0.25%), silicon (0.12%), potassium (0.08%), sodium (0.03%), copper, iron, sulfur, fluorine, aluminum, manganese, zinc, molybdenum and many other elements (27 in total). Interestingly, the composition of the eggshell is very similar to the composition of human bones and teeth.

Outside, the shell is covered with a layer of dried mucus - the shell membrane, which prevents the evaporation of moisture from the egg and the penetration of microorganisms. Inside there is a shell membrane that does not allow protein to pass through, delays the penetration of bacteria, but passes air, moisture and ultraviolet rays. And it is followed by an elastic protein film.

3. How does a chicken breathe in an egg through the shell?

The egg breathes through the pores in the shell. At first glance, the shell seems to be dense, but in fact it has a porous, gas-permeable structure. If you look at the surface of the shell through a magnifying glass, you can see many small pores through which air passes for the chicken. Through the pores, oxygen enters the egg, and carbon dioxide and moisture are removed to the outside. The shell of a chicken egg has about 7500 pores! There are more pores on the blunt end of the egg and fewer on the sharp one.

4. What is the thickness of a chicken egg shell?

The thickness of the shell of chicken eggs ranges from 0.3 to 0.4 mm, and it is not the same over the entire surface of the egg. At the sharp end of the egg, the shell is slightly thicker than at the blunt one. It is worth noting that the eggs of the same bird may have different shell thicknesses. The shell is thicker at the start of lay, usually in winter, and thinner from March to September. One of the reasons for the decrease in shell strength is the depletion of calcium reserves in the bird's body by the end of the laying season.

5. What determines the color of an eggshell?

The color of the egg shell depends on the breed of the laying hen. Interestingly, in most cases, hens with white earlobes lay white eggs, while hens with red ears lay brown eggs.

6. Which eggs are better - white or brown?

This question interests many housewives. In fact, there is no difference between brown and white eggs. The color of the shell of chicken eggs does not affect the nutritional value of the egg, its taste and quality. It also has nothing to do with the freshness of the eggs. However, it should be noted that brown eggs have a thicker shell, but blood stains are more common in them. Due to the stronger shell, brown eggs keep a little longer and are easier to transport without damage. Therefore, poultry farmers appreciate them.

7. How can you tell fresh eggs from stale ones?

You need to put the egg in the water. If it is fresh, it will lie at the bottom of the dish in a horizontal position. If the egg is more than one week old, then its blunt end will float up. An egg that hangs vertically in water is 2-3 weeks old, and an egg that floats up is 6-7 weeks old.

8. Why do stale eggs float?

The buoyancy of an egg depends on its freshness. The fact is that at the blunt end of the egg, between the subshell and albuminous membranes, a air chamber(fright). During storage, moisture evaporates from the egg through the pores, contributing to an increase in air space. Therefore, the longer the egg is stored, the more the size of the air chamber increases. That's why you should choose eggs with a matte surface, not a shiny one, when buying - this indicates the degree of their freshness. If the eggs are large but light, they have a large air chamber and are nearing the end of their shelf life. To determine the freshness of an egg in a store, you can shake it. If the contents dangle from side to side, such an egg is already spoiled and cannot be bought.

9. Why are eggs sometimes difficult to shell?

It turns out that it depends on the freshness of the eggs. The content of recently laid eggs adheres more tightly to the shell film, so fresh eggs are more difficult to peel. And if they lie in the refrigerator for a week or two, then after cooking they can be cleaned easier and faster.

10. Why do hard-boiled eggs sometimes have a grey-green yolk?

This happens if, as a rule, a not very fresh egg is boiled for too long or if it is not cooled in time after boiling. In overcooked eggs, the yolk shell becomes greenish. This happens because of the reaction of iron and sulfur, which are contained in eggs. When the eggs are heated, the sulfur from the protein comes into contact with the iron from the yolk and iron sulfide is formed at the junction between them, due to which a gray-green color appears around the yolk. The older the eggs, the faster this happens. Prolonged cooking and high temperatures also speed up this reaction.

11. Can you eat eggs with green yolks?

Yes, these eggs are edible. A greenish color on the yolk shell does not affect the taste of the egg and does not mean that it is spoiled. However, strongly overcooked eggs deteriorate in protein quality, so do not boil them for more than 10 minutes. To avoid greening of the yolk, use fresher eggs and refrigerate them immediately after boiling.

12. Why are there blood stains in chicken eggs?

Sometimes small specks of blood can be seen in the eggs. They appear due to the fact that the blood vessels burst in the laying hen and blood enters the yolk during separation from the ovary. Blood spots are more common in brown eggs. These blood inclusions should not be confused with the embryo. It happens that eggs have a blood ring on the yolk. This means that the embryo began to develop in the egg and the circulatory system of the chicken was formed (if the egg was stored at high temperature), but the embryo died at an early stage of development.

13. Can you eat eggs with blood stains?

Yes, these eggs are quite suitable for consumption. Blood droplets in the egg do not pose a threat to health and do not affect the taste in any way. But red spots on the surface of the yolk look unappetizing, so it is better to remove them with the tip of a knife before cooking. However, eggs with a blood ring in which the embryo has already begun to form should not be consumed in any form.

14. Which country consumes the most eggs?

Mexico ranks first in the world in terms of egg consumption per capita. According to Mexican experts, each resident of the country eats 21.9 kg of eggs per year, which is an average of one and a half eggs per day. Mexicans eat daily more eggs than in any other country. Japan used to be the world leader in egg consumption per capita. Each inhabitant of this country annually consumes 320 eggs, that is, approximately one egg per day.

15. Why does the yolk stay in one position in the middle of the egg?

The protein of a chicken egg consists of three layers: the outer and inner layers are liquid, and the middle one is denser. The protein around the yolk is denser than under the shell. In this layer, which is located around the yolk, elastic twisted cords are formed on both sides of the yolk between the blunt and sharp ends of the egg. It is these protein cords, the so-called hailstones or chalazes (Chalazae), that hold the yolk in the center of the egg, but do not prevent it from turning around its axis. Chalaza are formed from a dense protein, they can be seen on an egg poured in a saucer. Their ends float freely in the albumen - the curl from the blunt side of the egg floats in the layer of more liquid protein surrounding it, and the curl from the sharp side of the egg penetrates from the denser middle layer squirrel.

16. Why is protein sometimes opaque?

The cloudy white color of the protein is due to the presence of a large amount of carbon dioxide CO2 in the egg. A cloudy white is a sign of the freshness of the egg, as carbon dioxide has not yet had time to leave it. In old eggs, this element evaporates through the pores of the shell.

17. What are the yellow and greenish crystals found in egg yolk?

This is riboflavin (lactoflavin or vitamin B2) - one of the most important vitamins. Riboflavin is yellow crystals, poorly soluble in water. Egg yolk is one of the dietary sources of riboflavin. 100 grams of eggs contain 0.3-0.8 mg of riboflavin (vitamin B2).

18. Can you eat raw eggs?

No, raw eggs should not be consumed, let alone given to children. They can contain pathogens of many diseases, for example, salmonella bacteria, which cause food poisoning in humans, and sometimes severe forms salmonellosis with complications. Raw or undercooked eggs, as well as dishes with them ( homemade mayonnaise, pudding, some sauces and creams, egg smoothies) are potential sources of infection. Eating soft-boiled eggs or insufficiently fried fried eggs with a runny yolk can lead to unpleasant consequences. On the other hand, hard-boiled eggs, scrambled eggs, or well-done scrambled eggs will not cause salmonellosis or food poisoning. Bacteria can be found both on the shell and inside the egg, so it's important to cook it properly. Heat treatment kills germs. It should be noted that every year major countries more than 400,000 people become victims of egg poisoning, of which about 200 cases end lethal outcome. In addition, raw eggs do not benefit the body, as they are absorbed much worse than boiled ones.

19. What is food poisoning and what are its causes?

20. What are the signs of food poisoning?

The main symptoms of foodborne illness are abdominal pain, nausea, vomiting, diarrhea or constipation, bad taste in the mouth, headache and dizziness, often fever, severe weakness, and in severe cases - loss of consciousness. At acute poisoning already after 1-2 hours, the temperature rises, severe vomiting and loose stools appear, dizziness and weakness, the pulse becomes very rapid, the skin of the face turns white, the color of the lips changes, and with botulism, suffocation and respiratory arrest may occur. Therefore, when such symptoms appear, you should immediately call an ambulance.

21. How to avoid food poisoning when eating eggs?

When buying eggs, check the expiration date. It is better to buy eggs in a store - there is usually a date stamped on the shell. Check that the eggs are not cracked or broken - it is better not to use such eggs. If the egg is stale or has bad smell, it must be thrown away immediately and in no case be consumed or given to animals, otherwise you can get severe poisoning. In more fresh eggs less chance of salmonella growth. Natural defense mechanism inhibits their growth in eggs for 20 days. It is better not to risk and not drink raw eggs, do not cook soft-boiled eggs or fried eggs. Recipes using raw eggs should be avoided.

Bacteria can be both inside the eggs and on the shell, so eggs must be thoroughly washed before cooking. hot water(temperature 80°C) for at least 7 seconds. The fact is that Salmonella bacteria can get into the egg from the surface of the eggshell when it is broken. In addition, bacteria spread very easily to hands, dishes, tables, other foods and objects, so be sure to wash your hands before and after touching the eggs, and wash everything that touched the eggs after cooking. After you break a raw egg to prepare food, be sure to wash your hands. When cooking, never put raw and then cooked foods on the same plate. Even properly cooked food can be contaminated with bacteria if drops or small particles of raw food accidentally get into it. Make sure that the scrambled eggs or scrambled eggs are well fried and do not remain raw. Boil or fry semi-finished products (dumplings, meatballs and others) well. Processing food to perfection is the only way kill potentially dangerous bacteria and avoid severe food poisoning.

22. What is the most famous bacterium in eggs?

This is salmonella, which lives in poultry eggs, meat, milk and dairy products. Salmonellosis (or paratyphoid) is an acute intestinal disease, called various types salmonella, a very common form of food poisoning. The main route of Salmonella infection is through food. These bacteria multiply rapidly in foodstuffs (especially when warm), but do not change their taste and appearance. Salmonella accumulate in products of animal origin, tolerate drying, freezing, and survive in water for up to 2 months. They are resistant to smoking, salting, marinades, but quickly destroyed when boiled. Incubation period lasts from 2-6 hours to 2-3 days. Salmonellosis is characterized by gastrointestinal tract and the development of intoxication and is accompanied by diarrhea, nausea, vomiting, stomach cramps, headache, malaise, elevated temperature. In this case, you should immediately consult a doctor. Salmonella enteritidis (Salmonella enteritidis) is the most common type of such bacteria in many countries.

23. How many minutes does it take to cook eggs?

Salmonella are very resistant and die only with prolonged heat treatment. They breed at temperatures from +7 to +45 ° C, and the most best temperature for them + 35-37 ° С. At temperatures below +5°C, the growth of Salmonella stops. At +70-75°C salmonella die within 5-10 minutes, and when boiled instantly. Therefore, only hard-boiled eggs can be completely safe. Eggs should be boiled for 8-10 minutes from the moment the water boils, and scrambled eggs or scrambled eggs should be fried until dry.

24. At what temperature do egg whites and yolks harden?

Protein thickens at +60°C and hardens at +65°C. The yolk begins to thicken at +65°C and becomes hard at +73°C.

25. At what temperature should dishes containing eggs be cooked and stored?

Dishes containing eggs must be heated to a temperature of at least +70°C during cooking in order to kill bacteria. Re-heating food that has been stored for some time should also be at a temperature of at least + 70 ° C. Food should be stored at temperatures either above +60°C or below +10°C. Cooked food should not be stored at room temperature. At +20-40°C every 20 minutes the number of bacteria doubles and the risk of poisoning increases. A favorable environment for the reproduction of microbes is warm and humid. And the cold stops them from growing. Therefore, after eating, the remaining products should be immediately removed in the refrigerator.

26. How to properly store chicken eggs?

Immediately after buying the eggs should be put in the refrigerator. Eggs are recommended to be stored in the coldest place of the refrigerator (closer to back wall) separately from other products and in special packaging. Although most refrigerators have a dedicated egg compartment on the door, it is wrong to store eggs in the refrigerator door. Exactly this warm place In addition, the refrigerator is often opened and the eggs are exposed to frequent temperature fluctuations.

27. Why is it better to store eggs in a package?

Eggshells have thousands of pores through which odors can enter, as well as bacteria. Therefore, eggs must be kept in special trays and away from products with strong smell so they stay fresh longer. In addition, storage in egg trays will avoid the spread of bacteria from eggs to neighboring products.

28. What is the best way to store eggs - sharp or blunt end down?

Eggs are best laid with the pointed end down so that the yolks are centered. In this position, the eggs will be able to “breathe” and keep their freshness longer, since there are more pores at the blunt end through which oxygen enters the egg and carbon dioxide exits. In addition, there is an air space at the blunt end of the egg, in which there can be bacteria, and when turned over to the blunt end, they float up and enter the egg.

29. Can eggs be stored in the freezer?

No, you should not store eggs in the freezer - they will freeze there. The ideal temperature for storing eggs is +4°C.

30. How long do eggs keep in the refrigerator?

Fresh eggs keep in the refrigerator for 4-5 weeks from the date of production. It is not recommended to store eggs for more than 6 weeks, even in the refrigerator. Eggs are stored for a long time due to the fact that there is a protective film on their surface. Therefore, it is advisable to wash them immediately before cooking.

31. How long can boiled eggs be stored?

Hard-boiled eggs in the shell can be stored in the refrigerator for up to 7 days, but it is best to eat them within 3 days. Boiling destroys the protective film on the shell, which helps the egg to be stored longer. Egg dishes must be stored in the refrigerator. Egg salads are stored for 3-4 days, stuffed eggs - 2-3 days.

32. Can eggs be stored at room temperature?

You can, but it's better not to. Without a refrigerator, eggs spoil very quickly, even in one day at room temperature they lose their freshness. One day of storage of eggs at room temperature is equal to a whole week of storage in the refrigerator.

33. How much does one chicken egg weigh?

The mass of the egg ranges from 35 to 75 grams. The average weight of a chicken egg is 50-55 grams. This means that a dozen medium eggs can weigh 500-550 grams, and a kilogram will be about 20 eggs.

34. How much do egg white and yolk weigh separately?

The weight of the yolk is approximately 1/3 of the weight of the whole egg, and the weight of the albumen is 2/3 of the weight of the egg. That is, in an average egg, the yolk weighs 17 grams, and the egg white weighs 34 grams. And in one kilogram there will be 59 yolks or 30 proteins.

35. What determines the color of the yolk?

The color of the egg yolk - light yellow or bright orange - depends on the nutrition of the chicken. The carotenoids contained in chicken feed give yellow yolk. Carotenoids are naturally occurring pigments that are yellow, orange, or red in color. They give color to many plants, including vegetables and fruits. The more the chicken eats feed containing carotenoids (corn, alfalfa, grass meal), the brighter the color of the yolk. However, not all carotenoids give color to the yolk. For example, canthaxanthin and lutein impart a golden yellow color to the yolk, while beta-carotene does not affect the color. It should be noted that the color of the yolk does not affect the quality, nutritional value and taste of the egg.

36. What does the marking on eggs mean?

Each egg produced in a poultry farm and sold in a store must be labeled. Eggs are divided into dietary and table. Eggs are considered dietary for the first 7 days after they have been laid. Therefore, it is important to look at the date of manufacture. Such eggs are suitable for diet and baby food. Diet eggs after 7 days of storage are considered table eggs.

The first sign of the marking indicates the permissible shelf life:
- The letter "D" means a dietary egg, which is sold within 7 days.
- The letter "C" means a table egg, such eggs are sold within 25 days.

These periods are valid provided that the eggs are stored at temperatures between 0 and +20°C.

The second character in the marking indicates the category of the egg depending on its weight:
- "B" the highest category - 75 grams or more.
- "O" selected egg - from 65 to 74.9 grams.
- "1" first category - from 55 to 64.9 grams.
- "2" second category - from 45 to 54.9 grams.
- "3" third category - from 35 to 44.9 grams.

If the eggs are sold without any marking at all, you should not risk your health and buy them. Eggs of different categories differ only in weight, and their shell color may be different. In addition, some eggs come with two yolks.

37. And what determines the size of a chicken egg?

The mass and size of eggs depend on various factors. Chief among them is the age of the laying hen. Younger hens are more likely to lay small eggs, while older hens lay larger eggs. At first, the mass of eggs can be 40-50 grams, and by the age of the chicken it increases to 57-65 grams. The size of the eggs also depends on the breed and weight of the laying hen. Chickens that are underweight carry small eggs. Housing conditions, bird feeding, climate, season of the year and time of day of laying also affect the size of the eggs. For example, when warm weather chickens eat less, which often results in smaller eggs. Although sometimes young hens also carry large eggs or even eggs with two yolks. And it happens that in an egg they find large quantity yolks!

38. Why do chickens lay two-yolk eggs?

According to experts, eggs with two yolks are an anomaly. Double-yolk eggs are produced when two cells mature at the same time and pass through the hen's reproductive system together. Typically, such eggs are laid either by young laying hens that have not yet established reproductive cycles, or by mature birds (about one year old). The largest number hens lay two-yolk eggs in the first weeks of oviposition. The ability of hens to lay two-yolk eggs can be inherited. However, sometimes eggs with two yolks can be a sign of a diseased bird. If hens have problems with ovulation, inflammation of the oviduct, then they can carry eggs with two yolks, no yolk, too small or with various defects. Diseases of the oviduct in chickens can occur due to violations of the conditions of feeding and maintenance of laying hens, dampness and dirt in the room.

Eggs with two yolks are quite rare in nature and are not viable. They never hatch chickens. Previously, such eggs were considered non-standard and processed into egg powder. But then they began to be in demand among buyers, because they do not differ in taste from ordinary ones, but weigh more - 70-80 grams (while selected eggs weigh 65-75 grams). Therefore, chickens are now specially bred at poultry farms, which carry eggs with two yolks. Eggs with two yolks are completely harmless and suitable for consumption.

39. How many eggs does a hen lay in a year?

In one year, a laying hen lays about 220-250 eggs, and some hens lay up to 300 eggs or even more. It takes approximately 24-26 hours for a hen to lay an egg. Half an hour after the hen laid an egg, a new egg begins to form in her body. It has been noticed that white chickens carry an average of 45 more eggs per year than red or dark ones.

40. What determines the egg production of chickens?

The number of eggs obtained from a chicken for a certain period of time, that is, egg production, depends on the breed of the chicken, its age, conditions of keeping, nutrition, health of the bird, and also on hereditary properties and individual characteristics. For example, hens of egg breeds lay 10-12% more eggs than meat and egg hens and almost twice as much as hens. meat breeds. Hens of egg-laying breeds begin to lay their first eggs at the age of 5-6 months. Hens are able to lay eggs for about 10 years. But increased egg production is observed in the first year of laying, during which hens can lay 250-300 eggs. With the age of the bird, egg production decreases by 10-15% per year compared to the first year of laying. Therefore, on industrial farms it is economically profitable to use chickens only during the first year of laying, and on breeding farms - 2-3 years. And in the second or third year, only the best laying hens are left. Typically, a breeding flock consists of 55-60% young hens, 30-35% two-year-olds and 10% three-year-olds. Roosters are used up to 2 years, the most valuable - up to 3 years.

41. What does egg white consist of?

The egg block consists of water (85%), proteins (12-13%), carbohydrates (0.7%), fats (0.3%), glucose, various enzymes, vitamins of group B. Half of the protein contained in the protein is concentrated in an egg. It contains all the amino acids necessary for the construction of the protein of the human body, as well as lysozyme, a protein substance that kills and dissolves microorganisms, including putrefactive ones. But the protective properties of the protein are reduced during long-term storage. The protein is liquid near the shell and thicker around the yolk. Egg protein is the most easily digestible and complete protein found in food. It is considered a reference protein and other proteins are evaluated against it. Egg white contains approximately 17 calories.

42. What does the yolk of an egg consist of?

Egg yolk consists of water (50%), fats (more than 30%), proteins (16%), carbohydrates (0.2%), cholesterol and minerals. However, eggs are not fatty product, since the yolk contains more harmless unsaturated fats (70-75%), and saturated fats - about 28%. Egg yolk is rich in vitamins A, B1, B2, B3, B6, D, E, PP and others, and also contains phosphorus, potassium, calcium, chlorine, sulfur, iron, manganese, iodine, copper, cobalt. In addition, egg yolk contains lecithin, which is involved in metabolism and is necessary for normal functioning. nervous system. The yolk is covered on the outside with a thin transparent shell and consists of alternating concentric dark and light layers. The yolk contains about 60 calories, which is three times more than the protein.

43. What are the benefits of chicken eggs?

Eggs contain all the nutrients necessary for the normal functioning of the human body. This is an indispensable food product that is prepared quickly and is inexpensive. Eggs are an ideal combination of proteins, fats, carbohydrates, vitamins and minerals. Eggs are a valuable source of protein. One egg contains 12-14% of the recommended daily protein intake for an adult. The average chicken egg contains approximately 6.5 grams of protein (protein), as well as 5.8 grams of easily digestible fats rich in phospholipids, which are involved in the transport of fats in the body, are part of all cell membranes. The proteins and fats of chicken eggs are well absorbed by the body. Eggs are the only food that is 97-98% digestible. In terms of nutritional value, one chicken egg is equivalent to 200 ml of milk or 50 g of meat. For young children, this is the second most important product after breast milk. Eggs are low in calories - one medium egg contains 75 calories.

Chicken eggs are rich in vitamins, minerals and trace elements needed in the daily human diet. Eggs contain vitamins A, D, E, H, K, PP and B vitamins. They only lack vitamin C. They also contain phosphorus, chlorine, sulfur, potassium, sodium, calcium, magnesium, iron, zinc, copper, fluorine, manganese, iodine. Phosphorus is a part of all tissues of the body, participates in metabolism, affects the activity of the heart and kidneys, and is necessary for the normal functioning of the nervous system. Calcium is the basis bone tissue, found in the skeleton and teeth, affects blood clotting. Iron is involved in the processes of hematopoiesis, is necessary for the formation of hemoglobin, provides oxygen transportation in the body. Magnesium supports the normal functioning of the brain, is involved in the formation of bones and the regulation of blood sugar levels. Potassium regulates the acid-base balance of the blood, participates in the transmission of nerve impulses, improves the functioning of the heart and kidneys.

Eggs are a valuable source of folic acid, biotin, and choline, which is found in egg yolks. Folic acid (vitamin B9) normalizes the functioning of the circulatory system, supports immune system. Biotin (vitamin H) is part of the enzymes that regulate protein and fat metabolism. It improves the condition of the skin, hair and nails. Choline (vitamin B4) prevents the formation of fats in the liver, lowers cholesterol, activates the brain, improves memory.

44. Is it bad to eat eggs because of their cholesterol content?

Previously, it was recommended to limit the amount of eggs consumed due to the presence of cholesterol in them. But after a lot of research, it turned out that main reason elevated blood cholesterol levels is the consumption of foods high in saturated fats (mainly meat and dairy products). Eggs are relatively low in saturated fats, while egg yolks have more healthy fats that help cells function properly. Of the 5 g of fat in an egg, only 1.5 g of bad saturated fat, which contributes to the production of cholesterol, makes up for the harm from even this small amount of saturated fat. useful substances, which prevent the absorption of cholesterol by the body and contribute to its excretion. Choline lowers blood cholesterol, prevents the deposition of cholesterol on the walls of blood vessels. Choline is part of the phospholipid lecithin, which is an important component of body cells, helps maintain normal cholesterol levels, prevents the development of liver cirrhosis and cardiovascular diseases, and 50% of the liver consists of lecithin. daily requirement body in lecithin is about 5-6 grams. An egg yolk contains approximately 3.5 grams of lecithin per 100 grams of product (and 100 grams of lamb, beef or peas contain only about 0.8 grams of lecithin).

45. How many eggs can you eat per day or per week?

One egg, and it is in the egg yolk, contains approximately 215 mg of cholesterol, and daily rate cholesterol is about 300 mg. Therefore people with normal level cholesterol can safely consume 1 egg per day. At elevated level cholesterol or certain diseases (atherosclerosis, cholecystitis, liver disease) should limit the consumption of eggs to 3 pieces per week. When using butter, sour cream, fatty meat, sausages or nuts, it is also worth reducing the number of eggs eaten to 2-3 pieces per week. With an increased level of cholesterol, you can eat proteins, and refuse the yolks, because they contain cholesterol. It is interesting that it is in Japan, which is considered one of the world leaders in the consumption of chicken eggs per capita, that there is a record number of centenarians and there is the most low level cardiovascular diseases. Therefore, the previously popular prejudice about the dangers of eggs due to their cholesterol content has long outlived its usefulness.

“The color of the yolk depends on what the chicken is fed. For some reason, it is believed that orange yolks are healthier. Unfortunately, no matter how much we care about our nutrition, we do not always understand what food is actually healthy and what is not. You can pour something into the bird's food, and the yolk will turn red. Q: What's in the feed? Factories have their own fattening systems, the more production, the more these systems are tied to chemical additives. And in general, I noticed that in general, factory eggs are more whitish and faded in color, and farm eggs are more saturated in color. That is, the yellow yolk of a farm egg will be brighter than the yellow yolk of a factory egg. The other side of the coin is that farmers don't have the money for vaccines, and the birds need them, just like small children. Therefore, "healthy" farm eggs are very conditional. Personally, this picture is visually more pleasant for me: you break an egg, and the yolk is a juicy orange color. For me, such eggs taste more interesting, richer or something. But I'm not ready to overpay for it three times, especially since the benefits, as I said, are very conditional.

Alexey Berzin, chef at Cook'kareku restaurant:

“The color of the yolk depends on the diet of the chicken. Substances that affect color may be present in feed, for example, carotenoids, which are responsible for red hues: remember the same carrots. If the chicken just pecks at the grass, then the color of the yolk will be richer. But you won't notice much of a difference in taste. The taste also depends on the food, but not on color additives, but on the naturalness of the ingredients. Farm eggs with any yolks will taste better than industrial ones with orange ones. There is also a gastronomic sense in using eggs with different yolks: for example, creme brulee from orange yolks turns out to be very beautiful and bright. And many people visually like it when scrambled eggs with bright yolks are on the plate. But we, when choosing eggs for a restaurant (in Cook’kareku, eggs are present in almost every dish. - Note. ed.), were guided not by the visual component, but by quality: we take dietary eggs with a shelf life of up to 10 days and medium-sized ones (the older the chicken, the larger the eggs): it seems to me that small eggs are tastier.

Irina Nikulina, Chief Livestock Specialist at CJSC Sinyavinskaya Poultry Farm:

“The egg yolk is the most pigmented part of the chicken egg. The pigments in the yolk are carotenoids. These are very common in nature natural pigments of yellow, orange or red. The carotenes that give color to the yolk cannot be synthesized in the body of the chicken. Therefore, the main factor influencing the content of carotenes and, consequently, determining the color of the egg yolk, is the feed of the bird. It affects the color of the yolk and the age of the bird: the older the chicken, the less saturated the color of the yolk of her eggs.

If the bird's diet contains additives rich in yellow pigment, then the yolk will have a more saturated yellow or orange tint. This effect is given by corn of bright yellow varieties, grass meal. If you feed a chicken pale varieties of corn and alfalfa, the color of the yolk will be pale yellow. When feeding with colorless food, the yolk will also have a barely noticeable yellow tint. There are a lot of color options. And if you buy an egg with an orange yolk, there is no guarantee that the chicken was fed the right supplements and not chemicals. Therefore, it is not worth drawing conclusions about the quality of the product only by the color of the yolk.

This begs the question: why does the grandmother's eggs in the village always have a bright orange yolk? The answer is very simple: domestic chickens eat more grass, and it has a lot of beta-carotenoids, which are more active natural dyes. In the conditions of industrial poultry farming, feeds mainly consist of grains and can include up to 16 components, including grass meal. Here is such a complex dish being prepared for a bird.

So: the color of the yolk is not a sign of freshness and naturalness and does not affect the quality, nutritional value and taste of the egg. The widespread opinion that orange yolk is more natural and better than yellow is a delusion. And the color of the yolk does not depend on the color of the shell. No need to think that brown eggs have a richer yolk, and white ones are always paler. This is also a delusion.

But it's hard to argue about taste. And here's the thing, I guess. When we talk about food, it immediately seems to us that the dish should look tasty, which means bright. And here the orange yolk, of course, wins. But this does not mean that yellow is worse or not as tasty.

Often, egg producers try to feed hens with brightly colored foods to make the product look more attractive to the buyer. But if the bright color of the yolk was an indicator of quality, then all manufacturers would strive to achieve a color close to red. And that's not happening."

As you know, eggs have a different shell color, and the reasons for this diversity are completely different. The color of the egg shell does not always indicate the quality of egg products.

Factors affecting shell color

Around brown-shelled eggs, it is widely believed that they are of better quality and healthier. Many factors affect the color, but they do not affect the taste. To understand the dependence of color, it is necessary to understand what affects it.

Shell color in different breeds

Eggs of different breeds of chickens have their own characteristics and characteristics. White breeds of birds can produce white-shelled eggs. Such birds are especially common on large poultry enterprises, and in the store, eggs with a white shell color are in a predominant amount. The breeds of meat of the egg direction of productivity, common among the population, carry brown eggs, hence the myth that these eggs are natural. It's just that they are widely distributed on private farms.

The influence of the environment on the color of eggs

The color is influenced not only by breed predisposition, the reason for the color of the eggs can also be temperature, various stress factors, diseases. So the shade of brown is affected by a pigment such as protoporphyrin. A large amount of which is found in vitamins and hemoglobin. From how long the egg moves along the oviduct, the shell becomes saturated in color. This is because the pigment acts on the shell for a longer amount of time. The color is influenced by the laying period. Eggs laid for the first time are darker in color than next ones. The more pigment there is in the oviduct, the stronger the color of the shell. Therefore, the future color is related to the genetic predisposition of the bird.

Is there a difference between white and brown eggs

There is also a lot of speculation around these shell colors. Some people think that browns are healthier and tastier, as they contain a large amount of nutritional components. Cooks choose the dark color of eggs, believing that they are more suitable for confectionery dishes. But this is only a delusion, the differences between the two products are only in the color of the shell. The composition of the egg is the same, it does not depend on the color of the shell. Even the shell thickness is the same. There are differences, but they are not related to color, but to the age of the bird. Young hens lay eggs that have a dense and strong shell, their body is still young. Adult hens lay eggs with a less dense shell, as the body wears out.

If there is no difference, why are brown-shelled eggs more expensive than white-shelled eggs?

This is most likely a ploy by manufacturers based on the belief that brown eggs are healthier and tastier. But it is known that the bird that gives eggs brown shades consumes more feed, so the production of brown-shelled eggs is more expensive. Most of the eggs brown shells are found in chickens with a dark plumage color.

Why does it happen that eggs with different shell colors have different flavors?

The taste, again, is not related to the color of the shell, but directly depends on the diet that was given to the bird during the laying period.

Along with the shell, pay attention to the color of the yolk, the richer it is, the more useful the egg is. In fact, the color of the yolk is given by carotenoid pigments - vitamin A, which colors the yolk orange. This pigment is found in feed plant origin: herbal flour, corn, carrots. Using these feeds will produce an egg with an orange yolk.

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What can tell the color of an egg yolk? Surely many of you choose eggs with a bright orange yolk on the market, right? Is it worth it? What kind of eggs really the most useful?

Read the whole truth about egg yolks!
Everyone knows, probably since childhood, that a fresh chicken egg is a storehouse of vitamins and microelements, very useful and delicious product. We were told that what brighter color yolk, the healthier it is, right? Let's figure it out.

Which yolk in the photo do you consider the most useful, based on these statements?

The color of the egg yolk will change depending on the content of the chicken that laid it. This is no coincidence: the color of the yolk depends on the nutrients that the chicken eats.

Teno yellow yolk

Healthy, varied diet, free-range chickens that eat not only grain, but also green mass, worms, bugs, and breathe fresh air, and, most importantly, get the maximum sun - Better conditions that may contain chicken. These are home conditions. The yolk of such an egg is dark yellow, in the photo it is on the right.

The brighter the yolks, the more xanthophylls and fatty acids Omega-3, the greater the amount of vitamins A, D and E found in the egg.

pale yolk

On the contrary, if these substances are absent or insufficient in eggs, and the egg has a pale yolk, then there is no benefit in the egg, and protein and fats can be obtained from other products.

Farmers, poultry farms are interested in maximum profit, and therefore the attitude towards poultry is consumer: factory chickens “work” for wear and tear, do not see the sun and eat monotonous food, which at best consists of pure grain. These eggs are usually sold in supermarkets. This is the middle egg in the photo. These light yellow yolks are much less efficient at delivering nutrients to the body, meaning they are simply useless, though not harmful.

Bright orange yolk

The brightest egg, orange hue, and the most useful. Contrary to popular belief, the rich color of the yolk does not indicate an increased content of carotene, not all carotenoids can give color to the yolk. For example, the well-known beta-carotene is completely converted in the body of chickens into vitamin A and is consumed in metabolism. Therefore, beta-carotene does not affect the color of the yolk.

If the chicken is domesticated and receives grass, corn in the feed, and hay in winter, then her eggs will have a bright yellow yolk. If the chicken is factory-made, then the component of calendula, chamomile, nasturtium is added to the feed, which gives a bright orange tint, as in the photo on the left.