Cooking Eggs in Their Shells
(a.k.a., Hard-Boiled Eggs)

There is an art to cooking eggs in the shell that anyone can master. It is merely a matter of fully understanding the proper cooking technique and being aware of a few do's and don'ts. This article will discuss how to easily and successfully cook, peel and store hard-cooked eggs.

How to Cook Eggs in the Shell

Although they are often referred to as 'hard-boiled' eggs, eggs should not be boiled. If boiled or cooked too long, the protein in the egg toughens, becomes rubbery and a green-to-purple colored 'halo' will form around the yolk.

That 'halo' is caused by a chemical reaction between the iron in the yolk and the sulfur in the egg white. The catalyst is heat. The longer an egg is cooked, the more likely it will end up with that undesirable green ring. The objective is to cook eggs just until the yolk is set without overcooking them. Removing the eggs from the hot cooking water to an ice bath immediately after cooking will prevent the greenish-purple ring from forming.

The best way to cook eggs in the shell is to cook them in water just below the boiling point. This method is referred to as 'coddling' the eggs. Coddled eggs will not have tough whites, the yolks will be a beautiful yellow and they will be much easier to peel. The ice bath has a two-fold purpose. It not only stops the cooking process to prevent the halo but it will also make it much easier to remove the shells.

Cooking Technique for Hard-Cooked Eggs:

How to Peel Hard-Cooked Eggs

After cooked eggs have completely cooled in the ice bath, drain off the water and either roll each egg gently on a hard surface until the shells crack into many small pieces (the shell will be pliable) or cover the drained pan and shake it until the egg shells are cracked all over.

Hold each egg under cold running water to peel. This helps loosen the membrane between the shell and the cooked egg. It is important to get under the membrane in order to remove the shell smoothly and easily without tearing or pitting the cooked egg white. Start peeling at the large end of the egg.

Storing Hard-Cooked Eggs

Even though they are thoroughly cooked, hard-cooked eggs need to be refrigerated. Hard-cooked eggs in the shell may be refrigerated for up to one week. Those out of the shell should be used immediately.

Hard-Cooked Egg vs. Raw Egg...

Oops! Can't remember which eggs in the refrigerator are hard-cooked and which are raw? Have no fear -- just use this easy technique to determine which is which:

Gently place an egg on its side on a counter top or other level surface and give it a spin.

- If the egg spins freely, it's hard-cooked.

- If it wobbles and stops spinning, it's not hard-cooked.

(Note: Be careful not to spin the egg too close to the edge of your counter top.)

The following tips will only take a moment of additional preparation time and either one can also help prevent the 'Cooked Egg vs. Raw Egg' dilemma:

- After the eggs are cooked and cooled, mark an 'X' on the shells with a pencil before refrigerating. That way it can be determined at a glance whether an egg has been cooked or not.

- Add a few drops of food coloring to the hot cooking water as soon as the pan is removed from the heat source to tint the egg shells. There again, it will take only a quick glance in the refrigerator to determine which eggs have been hard-cooked and which are raw.

A Couple of 'Eggs-tra' Tips and a Final Comment...

(1) The consensus is that very fresh eggs are harder to peel -- the fresher the egg, the more the membrane will cling to the shell. To prevent this, use eggs that are a week to 10 days old. (Older eggs have a different pH from very fresh eggs and researchers feel that the pH directly affects peeling.)

(2) Remember, placing cooked eggs into an ice bath will stop the cooking process and also make eggs easier to peel, so don't skip that step when preparing hard-cooked eggs.

Please Note: It sounds quick and easy, but an egg cannot successfully be hard-cooked, in its shell, in a microwave oven -- it will, without a doubt, eggs-plode.