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What determines the color of the yolk and egg shell. What is the difference between white eggs and brown eggs

There is such an eternal kitchen dispute - which chicken eggs better: white or brown shell? Many are sure that brown eggs are definitely better, stronger, tastier and healthier. Yes, and in the store, brown eggs are sometimes more expensive than white ones with the same size and weight. What is the secret here? Are brown eggs really better, or is this just another big misconception?

Secrets of color

Why are chicken eggs so different in color? The color of the shell is a hereditary trait similar to the color of the feathers and depends on the breed of bird. Some breeds lay white eggs, others brown, others variegated and even blue, but in our area this is already exotic, which few have seen with their own eyes. However, sometimes even birds of the same breed lay eggs of different colors. Nature loves variety.

The brown color of the shell is due to the content of the protoporphyrin pigment in it, which is synthesized during its formation. Porphyrin pigments are widely distributed in nature. It partly affects the color of the egg and the diet of the chicken: with a lack of certain amino acids, the egg becomes lighter.

Which eggs are stronger?

The fact that brown eggs are stronger than white ones is a fairy tale. The strength of the shell does not depend on its color, it depends on the age of the chicken and its nutrition. The older the hen, the thinner the shell of her eggs becomes. With a lack of calcium in the diet of birds, eggs of any color “skinny”. Therefore, the owners of domestic laying hens introduce chalk, shells or special additives into their diet - so that the shell is strong. The same is true for large poultry farms.

But what about the yolk?

Everyone who has tried domestic chicken eggs notes that they are tastier than store-bought eggs. Usually the yolk of such eggs is brighter than the pale shop. And since homemade eggs are more often brown, does it mean that the yolk is brighter and tastier in store-bought brown ones? This is wrong.

The color and taste of the yolk also depends on the diet of the bird. A free-roaming and grass-pecking domestic chicken will have a brighter yolk than its counterpart from a poultry farm. Differences in the yolks of store-bought eggs different color No. Although you can make the yolk bright artificially by feeding the chicken with carotene, which is what some manufacturers do. But, of course, there will be no special nutritional value in such a bright yolk, except that the color is beautiful, but the taste is still the same.

Why are brown ones more expensive?

Like it or not, brown eggs are more popular, and the demand for them is higher. This is also a psychological moment - domestic chickens often lay brown eggs, so even in the store they seem better than white ones, I want to buy them. This can partly explain the difference in cost - increased demand. Another reason: breeds that lay brown eggs are more demanding on feeding and keeping conditions than white egg laying hens. They are larger, eat more and are more capricious in the choice of food, rush less. Hence the high cost.

Despite the variety of breeds of chickens, among which there are representatives of various colors, from blue-black to intense yellow, basically, laying eggs are laid in two colors: white or various shades of brown. What determines the color of the shell of a chicken egg? What makes the yolk yellow? Should I buy this product based solely on colors? The explanations of these issues are in the field of oology - the science that studies eggs.

Before moving on to color issues, you should understand the structure of the egg. Shell, protein and yolk are three components of a mature egg, which are in the ratio of 12:56:32 in relation to each other. If you do not take into account the outer shell, the proportion of albumen is 64%, and the yolk is 36%. Scientists came to the conclusion that 90% of the shell is filled with calcium carbonate, and the remaining 10% are magnesium, phosphorus, zinc, potassium, silicon, molybdenum, sodium, manganese, copper, aluminum, iron, fluorine, sulfur and other elements of the periodic table .

From the outside, the egg is wrapped in an over-shell film, which is a dried mucus. This protective layer prevents moisture from escaping and prevents exposure to harmful microbes. Inside is another "checkpoint": the shell film that holds the protein and serves as an excellent filter for microbes. However, it is open to the air and life-giving moisture necessary for the formation of the egg. The natural "checkpoint" is completed by a soft protein film.

The shell is 0.3 - 0.4 mm thick: at the sharp end of the egg, it is denser compared to the blunt end. The compaction of the egg shell also depends on the period of oviposition: at the beginning of the process, it is thicker, and gradually thins towards its completion.

The color scheme of the eggs, as well as the color of the plumage, are laid down at the genetic level. In chickens, like in other domesticated birds, the shade of the shell is due to belonging to a particular breed.

Brown color appears on the shell under the influence of protoporphyrin. Most often, this coloring matter can be found in hemoglobin and vitamins. He takes part in the synthesis of cells of the uterine mucosa during the formation of the shell, so the shade is laid at the initial stage of this process. How more hours is assigned to the egg's journey through the oviduct, the more intense its color becomes.

Factors affecting shell color

Partially for the color of eggs in one shade or another, the diet of birds matters: a lack of certain types of amino acids can lead to a decrease in color saturation. Also, its concentration is affected by the stage of oviposition, since the shade of the first eggs, as a rule, is more saturated. However, the most important factor affecting the color of the shell is the belonging of chickens to a particular breed.

It is enough to trace a parallel between the color of feathers and the color of the shell: females with white plumage produce white products, and speckled hens of other shades lay brown testicles.

Any variety of chickens is characterized by specific color characteristics. For example, the famous Leggorns or Russian Whites have snow-white plumage, respectively, their eggs will be of the same shade. Given that these breeds demonstrate excellent egg production, snow-colored eggs prevail on store shelves.

Hens Leghorn

Leghorn hens have been bred as an egg cross with high productivity characteristics. In addition, they have excellent adaptive abilities, have a moderate appetite and do not require much space in the chicken coop. We figure out how to properly maintain and feed "leghorns". And in the article "" let's take a closer look at dwarf chickens.

In private farms, in order to increase economic profitability, meat and egg breeds are preferred, which have a predominantly fawn or brown color, like Rhode Island laying hens, for example. Therefore, a logical chain has become fixed in the minds of the average layman: brown eggs = homemade, which means a natural product. However, this formula does not work in practice.

There is a test method that gives a 100% result: a white earlobe is a guarantee of white offspring. Owners of red ears give products of brown shades.

The South American continent is the proud owner of an exotic breed of chickens that lay blue eggs with a greenish tint. In addition to the original color of the shell, the layers themselves also look quite unusual: they do not have tails. The absence of appendages on the back of the body, apparently, is compensated by a mustache and beard. The name of the Araucan breed comes from the Indian tribe of the same name, which breeds this variety of birds everywhere. A few decades ago, this outlandish product gained unprecedented popularity thanks to an erroneously formed stereotype. It was believed that in this product there are much more nutrients than in eggs of the usual shades, and the level of cholesterol, on the contrary, is much lower. However latest research refuted this consumer cliché.

Breeds of chickens Araucan and Ameraucan

Araucan chickens are known around the world for the unusual color of their eggs. However, many breeders believe that green eggs are not the only thing to love about this cross. Want to know what else is unusual about these chickens? Read our article on. By the way, the Araucans have a related cross - , which appeared by crossing Araucans with local American chickens.

In addition to breed, color saturation is affected by environment, the tendency of laying hens to various diseases and even stressful situations. These circumstances can significantly affect the intensity of color, giving the shell either a soft cream or a bright brick shade.

What determines the color of the yolk?

In addition to the color features of the egg shell, housewives are interested in the color of the yolk, which varies from light yellow to golden and bright orange. If protoporphyrin “worked” well on the brown shell, then the yellow tint is in the safe hands of carotenoids. However, not all representatives of this group of pigments have been given the power to color the yolk in bright colors. For example, the beta-carotene that makes carrots so orange has no effect on the yellow thick stuff. But pigments with unusual names lutein and xanthophyll are directly involved in the color of the yolk.

The coloring is due to the nutrition system: when chickens eat plants that contain yellow pigment in large quantities, the yolk will also acquire a more saturated shade. A similar effect can be achieved with saturated yellow varieties of corn or grass meal. If light varieties of corn or alfalfa prevail in the diet, the pallor of the color will be transferred to the yolk. If the diet is based on colorless feed, the yolk will turn out to be almost transparent, light yellow in color.

The color of the yolk, as well as the color of the egg shell, have absolutely no effect on the quality of the product. However, laying hen breeders try to give the yolk an intense color, so they feed chickens with food containing a yellow pigment. In addition, the researchers concluded that the yolk contains protein in greater quantities than the protein itself, therefore, its benefits in no way depend on the shade.

difference in chicken

When it comes to color, the breed of chicken is the key factor. Simply put, hens with white plumage will lay white eggs, while those with tawny plumage will lay brown. There are even breeds that lay the less common blue, or spotted, eggs.

Is a brown egg better than a white one?

Color is not an indicator of quality. If we are talking about taste and nutritional value, there is no difference between white and brown eggs.

Do brown eggs have thicker shells?

The shell of eggs of both colors has the same thickness. If you have ever noticed that the shell is thicker, this is the effect of the age of the hen that laid it. Younger hens lay thicker-shelled eggs, while older hens have thinner-shelled eggs. This applies to both white and brown eggs.

Why are brown eggs usually more expensive?

There is an opinion that browns are more expensive than whites because they are more natural. In reality, it is not. Brown eggs are usually more expensive, as brown-feathered hens are larger and require more feed.

Little nuance

However, there is one small nuance. Many people say that brown eggs are tastier because they have tasted brown eggs in the countryside. But even here color does not play any role - the fact is that in the villages you can most often find chickens with brown plumage, and a richer taste depends on the fact that domestic chickens are fed much better than those used for mass production of eggs .

I don’t know about you, but I definitely remember that in my youth it was always claimed that brown eggs were better and tastier. "Oh, you got the brown ones! They're rustic, delicious!" Wasn't there such a thing?

So, is it really true? Let's figure it out...

Due to the fact that brown and white eggs have different colors and prices (with the former always more expensive), there is a common misconception that they are different from each other. Moreover, many people believe that brown eggs are healthier because Golden Rule says brown is better. We prefer to consume brown bread, whole wheat and brown sugar because these foods are healthier than their white counterparts. However, when it comes to brown and white eggs, there is no nutritional difference between them. Okay, then what's the deal?

It's all about the chicken

The real difference between brown and white eggs is the hen that laid them. In the case of commercial chickens, there is a direct and distinct relationship between feather and egg colors. White-feathered hens always lay white eggs, while red hens always lay brown eggs. This rule also applies to other breeds of chickens, which can lay blue, green, and even speckled eggs.

The color of brown eggs is due to protoporphyrin IX, an organic compound that gives blood its red color.

The shell of blue eggs contains biliverdin; It is a green bile pigment formed as a result of heme catabolism.

It all comes down to the fact that the difference between brown and white eggs is associated with the presence of certain organic compounds. In terms of nutrition, brown eggs are no different from white ones - both in composition and in quality.

The environment affects the color and taste of egg yolk

While it's easy to argue that brown eggs taste better than white eggs - and vice versa - the reality is that it all comes down to how the chicken was fed and kept. For example, a chicken that has been allowed to roam in the sun during the day will get more vitamin D than one that has sat indoors. The same goes for chickens fed a diet rich in omega-3 fatty acids or vitamin D; their eggs will contain more high levels these components.

In addition, the way eggs are cooked and stored affects their taste. The longer an egg is stored, the more likely it is to taste bad. If you store eggs in the refrigerator at a low and stable temperature, they will keep their fresh taste longer. If you fry an egg from a chicken that has been fed a diet rich in fish oil (omega-3), it will taste the same as regular eggs, but if you boil it, it tastes beyond compare.

In conclusion: it is very important how the chicken is raised

You should pay attention to the labels on the egg cartons. Home-raised eggs are different from commercially-raised eggs. They are usually fresher. If you buy eggs that are rich in omega-3s, this means that the chicken was fed a diet rich in fish oil, and this is the main reason for the increased price. Finally, organic only means that the chickens were not given hormones or antibiotics, or were given only when absolutely necessary.

According to nutritionists, color in this case it does not matter and nutritional value is influenced by completely different factors.

So where did the myth of the superiority of brown and beige eggs come from? And what do you really need to pay attention to when choosing this product?

Let's try to figure it out together.

The most common myths about chicken eggs and the reason for their occurrence

We are already used to the fact that really high-quality food cannot cost a penny. Therefore, the fact that today specimens with dark shells have a higher price than light ones did not go unnoticed.

It is better to pay more, but get the maximum benefit - we think and reach for a more expensive tray in the store. And then we proudly carry it home and assure our loved ones that brown eggs are definitely more useful than cheap white ones. Unfortunately, the stereotype: “More expensive means better” does not work here. The nutritional value of light and dark eggs is absolutely the same. and cost has nothing to do with it. What are we paying for?

Myth #1. The higher the price, the more benefit

Let us immediately reassure that manufacturers are not trying to deceive us by offering identical products at different prices.

The fact is that breeds of hens that lay dark eggs tend to be larger and consume more feed. And since the maintenance of such a bird is more expensive, we are forced to partially compensate for the difference from our own pocket.

Myth #2. Brown ones look more natural, which means they are environmentally friendly.

This delusion comes from our childhood. In the villages, eggs of all shades of terracotta used to be served at the table, and white ones were rather an exception. Why?

The fact is that the color of the eggshell is directly related to the plumage of the laying hen. From a bird with a dark or variegated color, we will not get a white egg, but from a light one - brown. In the villages, chickens with golden brown, gray, black or pockmarked plumage predominated, which is associated with the peculiarity of local breeds. Let's remember our childhood. Have we seen many white chickens on the village streets?

Dark-colored laying hens were in favor for a simple reason: they belong to the meat and egg breeds, while the light bird belongs to the egg-bearing ones, that is, you can’t cook a rich broth from it, and the roast will turn out so-so - without a bright taste. Naturally, in home production it is better to have "universal" than "profile" chickens.

So we have a memory that before the eggs were brown, very tasty and healthy (our grandmothers often used them for medicinal purposes).

Today, the stores are dominated by products of large poultry farms. White eggs in industrial trays subconsciously seem to be of lower quality. This is true, but it's not about color, but about the lifestyle of laying hens. The villagers walked on fresh air, ate natural food, moved a lot. And what do modern birds see, rarely leaving the limits of cramped cages? Whether they lay white or brown eggs, their products will not be healthier.

The same applies to the brightness of the yolk. It differs in a more saturated color in poultry, as opposed to the inhabitants of poultry farms, whose conditions of detention are far from natural.

Myth #3. Brown eggs have thicker and stronger shells.

In fact, this figure depends on the age of the chicken. The younger it is, the stronger the shell will be and vice versa.

No less important is the lifestyle of the bird, its state of health and diet. not without reason farmers introduce various calcium-containing supplements as complementary foods: ground shell rock, chalk, shrimp shells, bone meal. These measures allow you to increase the density of the shell, make it more resistant to mechanical stress.

But the color here is completely irrelevant.

Summing up

To the question: which eggs are healthier, white or brown, we answer without hesitation - homemade. Main - .

Because they:

Eco-friendly. Chickens in small farms are free-range, eat natural food, do not receive chemical stimulants and antibiotics.
They have a rich taste and pleasant aroma. Even the simplest dish from such a product will decorate the family table.
Good for the health. Roosters live in poultry houses, so almost all eggs are fertilized and have the “correct” hormonal background, which has a positive effect on our body.

In order not to fall for the bait of dishonest sellers who offer, under the guise of home-made store products with erased stamps, you should only contact trusted housewives.

Distinguishing factory eggs is easy. They are the same in color and size, covered with a smooth, as if polished shell. In domestic eggs, the surface is slightly rough, the shade and shape vary (after all, all laying hens are different), and on the yolk there is a noticeably bright spot - the future embryo.

Why are some eggs white and others brown?

We have already said that the color of the shell is influenced by the breed of laying hens. Meat-egg varieties always have dark plumage, egg-bearing varieties always have light plumage.

Accordingly, the former lay eggs with brown shells of all shades: from almost beige to brick, and the latter only with white.

Finding out exactly which eggs this or that chicken will carry is not difficult. Just look at her earlobes. If they are light almost white, this is exactly what the shell will be. If it is deep red, the eggs will turn brown.

A bit of biology

Persistent terracotta shades are given to the shell by the pigment protoporphyrin. It is produced in the uterine tissues of the laying hen. The longer the egg is formed, the more intense its color, since the pigment is absorbed into the shell for a longer time.

The percentage of protoporphyrin in cells is laid down at the genetic level. That's why hens lay eggs of the same color throughout their lives, and its shades vary depending on the living conditions of the bird.

Note that brown and white are not the only color options for eggshells.

Chickens of the Araucan breed, very popular in the USA and European countries, lay blue and turquoise eggs. For this they were even called "Easter". The breed got its name from an Indian tribe, which, through a long selection, brought out unique laying hens, the uterus of which contains the pigment biliverdin, which gives blue and green color.
Marana laying hens are famous for their "products" with a deep chocolate hue. They were bred in the last century in France.
The British breed Legbar can fill our basket with eggs of three colors at once: turquoise, olive and cream.
Black chickens of the ancient Asian species Uheilyuy are a real exotic. They lay eggs that have not only a unique light mint color, but also healing properties. The extract from these poultry products can cure anorexia, hormonal disorders, cardiovascular diseases and problems with the immune system.

Regardless of color, eggs of all breeds of chickens have approximately the same nutritional value and taste. When buying, you should pay attention not to the shade of the shell, but to its cleanliness (there should be no remnants of chicken droppings or adhering feathers) and the absence of gloss. Besides, the size of the egg, its weight and category are important.

The most useful are considered small in size, but noticeably heavy specimens. They are carried by young hens. A product labeled "1" is recognized as the most balanced in composition.

Now we will definitely choose only the best!

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