Science of Eggs

 

From a health point of view, eggs are very interesting since they provide important lipids, proteins, vitamins, minerals, and trace elements. They are also a moderate source of calories (approximately 140 kcal/100 g), have a lot of culinary applications, and are reasonably priced. It has been found that eggs are the most affordable animal source of proteins, iron, vitamin B12, riboflavin, choline, and vitamin A. They are also the second most affordable source of zinc and calcium.

EGG NUTRIENTS

Eggs are among the foods with the most complete nutrition.
Whereas lipids, vitamins, and minerals are primarily contained in the egg yolk, egg proteins are split evenly between the egg white and the egg yolk. The majority of an egg is made up of water, and it is notable because there are no fibers in the egg. 

Egg structure: Eggshell membranes are edible but usually not consumed, as they remain tightly associated with the eggshell.

Basic composition of edible parts of the egg. (a) Egg white; (b) Egg yolk. 

Proteins: There is a significant concentration of proteins in egg white and yolk. The average amount of protein in one hundred grammes of whole, raw, fresh eggs is 12.5 g; in contrast, the protein content of one hundred grammes of egg white and yolk, with their vitelline membrane, is 10.90 g and 15.9 g, respectively.

Lipids Over 100 g of whole eggs, the total lipid content is largely constant, ranging from 8.7 to 11.2. Lipids are mostly found in eggs as phospholipids, linoleic acid, and arachidonic acid. While you can eat egg whites every day, you need be careful while consuming whole eggs because the yolk is high in cholesterol.

Carbohydrates: Eggs are minimal in carbs (0.7%) and do not include any fibre. 

Micronutrients: Vitamins and Minerals

Most vitamins are present in eggs, and more specifically, the yolk of the egg, with the exception of vitamin C (ascorbic acid). Because birds are capable of creating vitamin C from scratch from glucose, it's possible that the lack of vitamin C in the egg comes from this ability. Ten to thirty percent of human vitamin requirements are met by eating two eggs a day.
The average egg has 142 mg of sodium per 100 g, which is mild compared to the high levels of potassium, calcium, and phosphorus. Additionally, it has all of the necessary trace elements, such as zinc, copper, iron, magnesium, manganese, selenium, and iron; the main source of zinc and iron in it is egg yolk. 

Cooking: The most adaptable ingredient in the kitchen is the egg. The egg whites' protein coils unfurl and begin to form bonds with one another when they boil. The translucent whites become opaque (whitish) as the heat is applied more, and if the egg is overcooked, H2S gas will be emitted, giving the egg an unpleasant scent. The disagreeable green deposit you see between the yolk and white of an overcooked egg is called ferrous sulphide, which is created when the iron in the yolk combines with the hydrogen ions from the whites.
Advice: Salting the cracked egg at least 15 minutes before cooking will produce the fluffiest and softest eggs since salt unravels the proteins before they have a chance to cook.

References: Réhault-Godbert, S., Guyot, N., & Nys, Y. (2019). The Golden Egg: Nutritional Value, Bioactivities, and Emerging Benefits for Human Health. Nutrients, 11(3), 684.

Masala Lab (2021)