EGG CONTENT - WHAT IS THE EGG MADE OF?
Egg is a very versatile ingredient but it has to be used under certain constraints, which we will discuss on the next page. To understand the egg better though we will first bring up some information about what an egg is made of. As we all know, an egg has two major parts - the white and the yolk. The biological function of the yolk is purely nutritional - it contains proteins, iron, vitamins, all embedded into special kinds of fats. The reason the yolk is yellow is because of the food that the hen eats. Unless the producers don't add some extra pigments to the hen's food, the yellow stuff comes from carotenes (plant pigments) that can also be found in fruits or carrots. The yolk can be seen as a bag of tiny particles composed of water, proteins, cholesterol, and lecithin (a kind of molecule that is involved in building up cell membranes). Now, it has been said that the high amount of cholesterol in egg is deteriorating for our health, but research has shown that it might not be that bad: it seems that other fats and proteins in the egg inhibit the uptake of egg cholesterol in our intestines. It is far worse when it comes to meat cholesterol, even though the amount of cholesterol in meat is lower. The problem is that people eat high amounts of meat, so...
When it comes to the egg white, it is a very different story. Virtually fatless, but still packed with proteins, although these are the proteins of a different kind. Without going into small details, they protect the egg yolk (or the growing chicken) from microbes, they make the water more viscous and thus provide the cushion for the inner life, and of course, these proteins coagulate when heated, which is when they become a white opaque, firm mass. The color of natural uncooked egg white is yellow-green, a result of the relatively high content of riboflavin (used in our bodies for key metabolical molecules). Egg white also contains a pinch of glucose that doesn't really suffice to make the egg white sweet, but in longer cooking times it becomes one of the key molecules that provides extra flavor to the egg.
The wide belief that eggs are not so good for our blood cholesterol, which seems not to be true, made some companies to start producing egg substitutes. They are cholesterol-free, but the rest of the product is essentially imitating the other egg ingredients. Usually, natural egg whites are combined with oil, milk proteins, and some thickeners, plus some flavorings and colorings. Egg substitutes can be used in baking, scrambled eggs, and for omelet making, that is, no solid "egg-looking" dishes.
The most simple (?) dishes to make based on eggs are scrambled eggs and an egg omelet. The preparation of the dishes is however quite different. Since many people's idea of scrambled eggs is a lumpy mass of rubbery eggs (essentially the same idea as for an omelet, but with different shape), we might need to give some advice on how to improve these dishes. A major rule here is the temperature. When we make scrambled eggs we need to keep the temperature low and stir the eggs continuously. One way to make this dish is to melt the butter on low heat until it just starts to bubble and then add the eggs and start to stir, until they are almost set and firm. The final product should be slightly runny, not lumpy. For an omelet, the temperature should be high, for example when the butter has stopped sizzling and the heat is good. As we add the eggs, we let them set for a few seconds to create a thin coagulated layer at the bottom of the pan, then we continuously stir the rest of the egg mixture that's on top of this layer. The omelet should be cooked really fast, within one minute or so (in contrary to scrambled eggs!). When the eggs are almost settled - they should be slightly runny and tender (no overcooked rubber!) - the omelet can be put down on a plate. The residual heat in it, as in scrambled eggs, will continue to cook the eggs for another while, so timing for removal of the pan from the heat is very important.
Needless to say, there are a number of ways to make an omelet, and we all have our favorites. The same goes for scrambled eggs. It doesn't really matter which way we choose, as long as the result is satisfactory!