Composition of chicken eggs. Chemical composition of chicken eggs

Since ancient times, eggs have been traditional Slavic food. They symbolize the revival of nature and spring, so for every Easter people cook krashenki and pysanka, and the celebration traditionally begins with a sacred egg.

general information

Egg is a protein product with very high nutritional and biological value. Eggs of water birds are not used in cooking, as they can cause infectious diseases. The chemical composition of the chicken egg includes protein (12.7%), fats (11.5%), carbohydrates (0.6%), mineral salts (1%), water (74%), vitamins D, E, carotene, Choline and many other substances. The energy value of one hundred grams of eggs is about 157 kcal. For nutrition, one egg is equal to 40 grams of meat or 200 ml of milk.

Shell

Chicken egg consists of 12% of the shell, 56% of protein and 32% of yolk. The shell has a porous structure that protects the product from harmful microorganisms. The composition of the eggshell shell includes calcium carbonate, phosphoric acid calcium, magnesium and other organic elements. Under it there is a dense shell-like shell, the main component of which is the protein. The shell helps protect the egg from getting sick of pathogenic microflora, but nevertheless it passes gas and water vapor. At the stupid end between the shell and the protein shell is an air chamber, which for prolonged storage of the egg increases, as its content dries.

Protein composition of chicken egg

The protein consists of many layers of a transparent viscous, almost colorless liquid that foam when whipped. The density of protein in the egg is not the same, the densest is in the middle, near the yolk, as it keeps it in the center.

The protein contains many elements, among which, in particular, there are ovalbumin and conalbumin. These substances contain many amino acids that are in optimal proportions. This leads to the fact that eggs are 98% absorbed by the body. Ovoalbumin guarantees high protein solubility in water; Vegetable globules promote the appearance of foam during whipping; Ovomucinum stabilizes the foam. Also an important element is lysozyme, which has bactericidal properties that disappear when aging eggs.

The protein contains a lot of minerals. It also contains vitamins B1, B2 and B6. The energy value per 100 grams of product is 47 kcal.

Ingredients of egg yolk

The most valuable part of the egg is, undoubtedly, the yolk. This is a thick liquid, consisting of light and dark alternating layers. On top of the yolk is covered with a very thin protective shell, and on the surface of this part of the egg is the embryo. The yolk contains many proteins (16.2%), fats (32.6%), carbohydrates and minerals. The yellow color is given to carotene, which, getting into the body, is transformed into vitamin A.

Composition of chicken eggs. Useful substances and their effect on the body

The chemical composition of chicken eggs includes the protein avidin, which binds vitamin H (biotin), regulates neuroreflex activity, forming the Avidobiotic complex. With thermal effects, the complex decomposes into its constituent elements, that is, a constant intake of raw eggs can lead to H-vitaminase, which can adversely affect health.

Protein ovomukoid, which is also part of the egg, destabilizes the work of trypsin, the enzyme of the pancreas, resulting in poor assimilation of not only the egg itself, but also other foods. In addition, since ovomucoid can be absorbed by undigested, regular use of it can lead to the appearance of allergic reactions. This is especially true for children, because their immune system is weaker than in an adult. When heat affects the properties of ovomucoid completely disappear, and when whipped - significantly reduced.

The enzyme lysozyme, which is in the protein, if the storage conditions are not observed, can be destroyed, which leads to the propagation of harmful microorganisms. For this reason, eggs can become a source of severe infections.

Nutrition

The composition of chicken eggs includes a large amount of fats, most of which are concentrated in the yolk. They have a very low melting point, therefore, they are perfectly absorbed by the human body. The yolk also contains unsaturated fatty acids, such as arachidonic, linoleic and oleic.

The eggs contain a small amount of cholesterol, about 1.6%, which, however, can accelerate the development of atherosclerosis. Therefore, it is recommended to people of old age to reduce consumption of eggs.

Classification of eggs

Chicken eggs are divided into categories according to such criteria as shelf life, weight and quality. Diet eggs should be realized within 7 days after they were demolished, and dining rooms can be stored for longer. The composition of chicken eggs causes such tight storage times. Table eggs, in turn, are divided into fresh, refrigerated and limed.

Dietary eggs

This subspecies has a very small yolk, located in the center, and the protein is dense. The air chamber does not move. There are two categories that differ in weight: 1st category - not less than 54 grams, 2-nd - not less than 44 grams. On each egg there should be a stamp on which the production date, type and category of the product are indicated.

Fresh, refrigerated and limed eggs

Eggs that belong to the categories of fresh, refrigerated and limed, have a yolk small, but viscous, a slight deviation of its position from the center is permissible. The protein should be dense, and the size of the air chamber - no more than 7 mm.

Fresh eggs are those that were stored for no more than 30 days at temperatures from -1 to +2 degrees; To refrigerators - stored more than 30 days. Limestones are eggs that are stored in lime for any period.

The most valuable for consumption are dietary and fresh eggs. The reason for this is the composition of chicken eggs, all useful substances of which are preserved during short-term storage. They are consumed in absolutely any form. Refrigerated and limed eggs are also used for making confectionery and bakery products.

Melange and egg powder

At mass food enterprises, not only chicken eggs, but also processed products are used for cooking: melange and egg powder.

Melange is a mixture of mixed yolks and proteins that have been filtered, pasteurized, cooled and frozen at a temperature of -18 degrees. From this product prepare dishes that do not require the separation of protein from the yolk, for example, dough for various pastries. To replace one egg, you need to use 40 grams of melange.

Egg powder is a mixture of dried proteins and yolks. It is used for the same dishes as melange, but with proportions of 1: 0.28.

Conclusion

The chemical composition of a hen's egg determines the terms and conditions for its storage both at home and on a production scale. Nevertheless, it is necessary to ensure that in the refrigerator eggs are away from products that have a pronounced odor. This will provide optimal conditions that will help keep the product in a usable state.