The 6 types of eggs (characteristics and benefits)

In biology, an egg is a rounded body of variable size and hardness that protects the embryo from the harsh environment while it develops. Eggs are typical reproductive structures of birds and reptiles, but amphibians, fish and invertebrates also use them to leave their offspring, although these do not respond to the typical shapes (they are usually viscous or soft, small and not always circular).

The egg corresponds to a clear evolutionary mechanism that marks the development of aquatic and semi-aquatic animals: oviparity is a clear survival advantage in reptiles and birds, because as the environment is dry and arid, the embryo can develop correctly with a minimum energy cost and its shell avoids the desiccation and entry of possible pathogens.

Along these lines, we are going to focus our attention on the unfertilized eggs produced by domestic chickens (Gallus gallus domesticus), the subspecies of the wild rooster with which we are all familiar. This is a food with excellent nutritional values ​​that should not be missing in any non-vegan diet

: stay with us, as we review the 6 types of eggs and their properties in the following lines.

• We recommend you read: "14 healthy and easy to prepare vegetarian recipes"

General information about the egg

Female hens lay an egg every 24-26 hours, regardless of whether or not it has been fertilized by a male. In nature, the hen lays as many eggs as possible (10 to 12) to fill the nest, but the reality is very different in captivity. In production farms, each egg is removed as soon as the poultry farmers detect the laying, so the female lays more indefinitely, since her nest is never filled. This (and the genetic selection of specimens) allows us, as a species, to have an unlimited source of eggs, as long as there are chickens.

The chicken egg is made up of three basic parts: shell, white and yolk. The shell accounts for up to 15% of the total weight of the egg and its nature is mineral (94% calcium carbonate). This hard but permeable physical barrier plays a very important biological role, but since it is not edible, we are not going to dwell on it any longer.

The white, on the other hand, is a viscous medium rich in water and proteins. (up to 15% protein material) that protects the embryo during its development from mechanical stress and provides it with an accessory source of nutrients. The yolk, without a doubt, is the most important part of the egg: it contains the germinal disk (from which the will develop the fetus) and the yolk, which is truly the largest source of nutrients in this entire conglomerate biological. Contrary to what is usually believed, the white is not the cytoplasm of the ovule: this position is occupied by the yolk, which is within the yolk itself.

• We recommend you read: "25 High-Protein Foods (And Their Benefits)"

How are eggs classified?

If we had to choose one of the parts of the egg as a "superfood", it would undoubtedly be the yolk. In any case, it should be noted that there are different types of chicken eggs, depending on the place of origin of the mothers, the rearing method and many other things. Next, we present the 6 types of eggs.

1. White egg

The white egg is the one we all know, well it is present in practically all food retail outlets. We take advantage of this generic egg to provide you with a series of general nutritional facts about this food:

100 grams of boiled egg (two units) report about 155 kilocalories. If they are fried, an additional 90/100 kcal should be added, due to the absorption of oil.

• Of its total weight, approximately 12.8% are proteins, 0.7% are carbohydrates and 12.1% are lipids, generally monounsaturated.
• The white contains many vitamins: it reports between 10 and 20% of the recommended daily amount of compounds such as vitamins A, E, D and K.
• The egg also has other essential micronutrients, such as phosphorus, selenium, iron, and zinc.
• The nutritional value of the egg yolk is considered as a standard of nutritional perfection from a protein point of view, as it contains all the essential amino acids in proportions suitable.

2. Brown egg

No matter what they try to sell you: nutritionally, a brown and a white egg are exactly the same. The only difference lies in the phenotype and genotype of the mother, since the white hens lay white eggs and the brown ones, brown. The nutritional value of an egg never depends on the color of the shell or the shade of the yolk: these parameters are conditioned by the rearing of females, something that cannot be observed with the naked eye in the egg.

3. Organic production eggs (type 0)

In the world of livestock, there are two main types of production: intensive and extensive. In the first variant, artificial structures and means are used to raise the animals, above their welfare and physical integrity. Under these conditions, the birds are usually crowded into small dens and are fed with I think synthetic, since the production is valued above the animal ethics and the nutritional value of the product.

In extensive ranching, natural pastures and foraging areas are used to raise the animals. animals, which results in a product of much higher quality, although with slower production and lower costs. elevated. For an organic egg to be considered as such, must present the seal of "organic product" of the European Union, a symbol exemplified by a green leaf made up of stars. If not, the qualifier "ecological" does not reflect anything.

4. Free-range eggs (type 1)

Free-range eggs come from chickens that live with more space at their disposal and are calmer than the crowded ones in an intensive production environment. According to European regulations, these birds must have access to the outside and have a minimum space of four specimens per square meter (which increases to nine in the hen house).

The main difference between organic and free-range hens is their diet, since the latter receive a more controlled diet (less organic) with a higher content of drugs. In addition, the density in an ecological chicken coop is lower than in a free-range one (it goes from nine individuals per square meter to six).

5. Ground-raised eggs (type 2)

In this section, we already enter the fields of intensive and non-extensive livestock production. A ground-raised hen is one that never sees real sunlight or has access to the outdoors., but at least it has some surface area available to move around and perform its functions to a minimum. The maximum density is nine specimens per square meter of soil, but the food is in all cases I think not natural and the animals are subjected to medical and / or hormonal treatments typical of livestock intensive.

6. Cage Raised Eggs (Type 3)

This time, the hen does not leave a cage-shaped den at any time in its life. The difference between the method of rearing in the ground and in the cage is only ethical, since the feed given to both hens is the same and the overcrowding conditions are similar. The only thing that differentiates one case from the other is a slightly greater freedom of movement in the case of soil rearing, but this does not have to translate into better nutritional values ​​of the product.

Resume

As you have seen, the world of eggs contains more secrets than it might seem at first when it comes to consumption. The shape of the egg, its color and the morphology of the yolk say little about the nutritional quality of the product.. If we really want to find out its reliability, we must focus our attention on the eco-label endorsed by the EU and the means of egg production.

An organic chicken egg will always be better, because the natural foods that the hen consumes in semi-freedom translate into more adequate vitamins and minerals than a fatty feed designed to lower costs of production. Unfortunately, these products are always more expensive than those obtained through intensive farming and come less units per container.