Cooking an egg properly is not as easy as boiling water. You can ruin eggs, or dishes containing eggs, in seconds, and there’s no bringing them back to edible. The major problem in cooking eggs is that they are as sensitive to heat as rubber-and heat them too fast or just a little too long, and they’ll will be like eating rubber. But first let’s explore their uses.

Besides being a good source of nutrition, eggs also perform three culinary tasks with profound significance in western cookery:

1. Binding-for example, in custards the yolks and whites act together to thicken and bind other ingredients in the liquid. You activate this by low heat until both coagulate, solidify and incorporate the rest of the ingredients into their structure.

2. Emulsifying-for example, in mayonnaise, salad dressings and hollandaise sauce. It is the egg yolk that permanently suspends oil in water. Yolk is an emulsion, which makes it an efficient emulsifier with other ingredients. Emulsions are complex systems that form according to physical and chemical laws.

3. Foaming-as in sponge cakes and soufflés. The albumen in the egg white is able to hold enormous quantities of air in its structure when you beat it, and it forms a semistable foam. Here beaten egg whites act alone in two similar capacities-as leavener to give a light, airy texture and as a semisolid network of support to give structure to the baked product.

Eggs are useful in two other ways: they lend their delicate yellow coloring to whatever you bake with a yellow pigment (xanthophyll) in the yolk and, secondly, they also act as a glue for breaded foods. When the egg coagulates in the heat (oven or deep-fry oil), a tight adhesion forms between the food and the breading material.

Cooking whole egg in the shell

If you can boil water, you should be able to boil an egg, right? But cooking them and ending up with easily peelable shells and perfect, bright yellow, still-moist yolks in the dead center of the whites is somewhat trickier.

First, let’s straighten out our terminology. The American Egg Board declares that there is no such thing as a hard-boiled egg. Eggs simply should not be boiled, the egg people maintain. It is a hard-cooked egg that we are after, and we accomplish this by cooking them in barely simmering water or letting the eggs stand in water that is just been brought to boil.

Although the American Egg Board may be correct, the terms hard-boiled and soft-boiled are too firmly entrenched in our kitchen terminology to change. An overcooked egg has a dry and discolored yolk. Too much heat eventually breaks down proteins, and discoloration occurs as these react with sulfur and iron compounds in the yolk.

To avoid this fate, set your timer and cook an egg no more than 10 minutes. A centered yolk is critical only when you are planning to cut the cooked eggs in half. The Egg Board says storing eggs pointed end down gives a better chance of a centered yolk. Egg packers always pack

To peel the shell off both easily and fast, leaving a fully intact egg behind is visually important for some recipes, especially hors d’oeuvres. Nothing is more frustrating than trying to remove a shell that won’t let go of the egg white. You end up with an egg that looks like an outer-space-pitted meteorite.

Let’s look at the physics of what makes one egg peel readily and another cling to the shell as if its life depended on it. I discussed above the two membranes that is between the shell and the white.

First, the fresher the egg, the stronger the bond of the outside of those two membranes. With aging, the membranes shrink and the bond weakens. Because of that strong bond, hard-boiled fresh-laid eggs are the toughest to peel. Once they are about a week old, the membrane’s bond begins to weaken considerably. That is one thing you don’t need to worry about when you buy eggs at the supermarket. No eggs are likely to be less than a week old by the time they hit the supermarket shelf.

Not only their freshness, but the way you cook eggs can also affect the shrinking of the membrane. First, bring eggs to room temperature before cooking them. Starting with cold eggs ups the chances of cracking while in the cooking water because there is too much temperature change.

Eggs should warm up in an hour or two on your counter (depending how warm your kitchen is), or in a pot of very warm water in a few minutes.

Place the eggs in a cooking pot. Fill the pot with water to about an inch above the top of the eggs. (Adding salt to the water, as some cookbooks recommend, does nothing to aid in peeling, and it doesn’t help the flavor, either. The salt does not penetrate the shell.) Turn the burner on high and keep an eye on the pot. As soon as the water starts to boil, put the lid on and reduce the heat. Simmer in barely bubbling water for 10 minutes.

Remove the eggs from the hot water with a slotted spoon (don’t pour the hot water off yet), set them in a bowl and run cold water over them for half a minute to give them the shock of their lives (this helps prevent yolk discoloration, too), then put them back in the hot water for another half a minute for another shock.

Drain the hot water and place the pot under running cold water until the eggs feel cool, 3 to 4 minutes. The shocks should shrink the fine membranes enough to separate them from the shells and the eggshell should come off easily, but don’t be in a hurry. If you have the time, the shell comes off even easier if you let the eggs chill for a few hours.

The first step in peeling is to place all the eggs in an empty pot, cover with a lid and shake them gently up and down and side to side, so they bang against the pot and each other. This shatters the shells into a network of cracks, another help to peel. Be gentle so the eggs themselves don’t break. The shells are now as easy to remove as freshly blanched tomato skins.

Soaking the eggs in water for half hour after cracking them is also helpful if you have the time. The water seeps in under the shells, and they almost fall off by themselves. Peeling under running water or in a large bowl of water is another good idea. Start peeling at the flat end as that is the end that contains the air pocket.

Peel the shells off so the membranes remain with the shell, not on the egg white. Food industry egg peelers who peel eggs by the thousands, day in and day out, use this technique, piling the perfect oval, shiny, nude eggs in small mountains. No machine

has yet been invented for this job that can match the human touch.

Soft-boiled eggs

Soft-boiled eggs are simple because you don’t need to worry about easy peeling. Bring them to room temperature before cooking to avoid them shocking in boiling water and the shell cracking. If you are in a hurry, place refrigerated eggs in a bowl of very warm water.

In 10 minutes they will be near room temperature. When the water is boiling, slip the eggs in the pot one at a time with a spoon and start the timer. Cover the pot and keep the water on a gentle simmer. For large eggs, 4 minutes of cooking gives you firm whites with runny yolks in the middle.

Adjust this time half minute either way for softer or firmer eggs. Similarly, adjust the time if you use smaller or larger eggs than the standard large size.