By Hervi This

Recipes:
[Moscovite Tuna in Crystallized Tomato]  [Sardines "in a Box" with Eggplant and Cumin]

[World of Chefs] [www.thuries.fr]

This month, you see me distressed. I asked for critiques, I shouted to begin a debate, I asked for advice, so that this column would suit you perfectly … and nothing!

I am left to myself to find a response. Sometimes, a reader of Thurihs Magazine will write to tell me that he favors the most technical of my articles, but, still I bend to the will of my desires. So to punish you, let ramble - let me speak to you the hard-boiled egg.

Yes, you read correctly! In Thurihs Magazine, in this newspaper dedicated to the highest gastronomy, I will become the heretical chemist (for the world of the kitchen) and inflict upon you the benefits of hard eggs.

We will make hard eggs, but this time we will look for the perfect hard one. This egg, for which I am ready to pay at the cost of the caviar if it carries a memory that I will cherish all my life, how will you cook it?

I regret that writing doesn't permit me to leave some silence: I would like to let you the time to think there. Then I would repeat the question so that you have the time: how would you make me a perfect hard egg?

There are those who will tell me that the perfection is not of this world, and they will be right. Bu they should remember Jean-Anthelme-Brillbt-Savarin, who wrote: "The soul, reason always active of perfectibility".

We have a soul, lso et's look for the perfection in accordance with what Malebranche wrote: "One must aim with effort to the infallibility without pretending." And let's not forget non Watson, who wrote with reason that, "Better it is to aim for and miss  perfection than to reach for mediocrity."

Yes, a hard egg will never be perfected, not because it is impossible, but because its existence is as a matter of impossibility: each person has his tastes, each his own perfect hard egg.

If I succeeded in making a perfect hard egg, could I change some parameters for example, to make yours also? Perhaps, so let's analyze mine. My ideal hard egg, to me, must not be cracked. Then, it must be peeled easily. The white must be cooked thoroughly, tasy bnut not rubbery.

Its yolk must be cooked without being "sandy". It must not have any odor of sulfur and must not be green. Finally, the yolk must perfectly be centered in the white. Imagine that an inspector ask me for a hard egg - would it now be necessary that the symmetry is perfect? How does one to get all these qualities that will almost make of our hard egg a perfect object?

First the egg must not break. But how does one ensure this? Is it necessary to consult the Ancients? Revere them, believe that they knew all, yield to the myth of the gold age, and believe that tradition is an absolute guarantee. In this case, the tradition says merely that it is necessary to put salt in the water of cooking. The magic of salt, which was nicknamed the white gold. But will this stop the eggs from cracking?

Let me consider the tradition. Not that I want the revolution in kitchen, but I ask for the exercise of the reason. Besides, when I write that the tradition counsels to put salt in water, I am wrong, since the books of the past are not unanimous on this point. Then, what remains if the tradition is not a sufficient guarantee? Experience. The simple experience that should be the keystone of the kitchen. Experts tells us, moreover, that salt acts by a "osmotic" effect: a very big word to say merely that it would stop water from entering in the egg; water would inflate the contents of the egg and crack the shell. The experience is simple: let's put 20 eggs in the pure water, and twenty eggs in the salty water, then, at the end of cooking, let's count cracked them. There is no difference! In short, salt in the water doesn't stop the eggs from cracking. On the other hand, a chef in  England recommends puncturing the eggs, making a small hole in the shell. You can use a needle and you will see, under cooking, air escaping the egg in big bubbles. It is this, the expanding air, that cracks the eggs.

Egg shelling simplified

Now we come to shelling. The books mention heaps of interesting things: that eggs shell better if they are cool, that eggs shell more easily if one puts them in the cold water. That I know, but I don't always have any perfectly cool eggs. With students at the University of Tours, we tested the byword of the cold water… and we didn't see an effect.

So what do we do? Let's examine the "eggs of a hundred years," these eggs that the peoples of Asia leave for three months in the lime or in the ash. The ash contains potash (or hydroxide of potassium), and the lime is a hydroxide of calcium. These hydroxides are basic compounds, the opposite of acids. So it is natural to ask a chemist: what happens when one puts some eggs in an acid?

To experiment, I first propose you to take a cool egg and to immerse it completely in vinegar. You will see some small bubbles forming on the shell. The limestone is attacked by vinegar. What happens then will be the subject of another chronicle, but you see it, to idle about is sometimes fruitful: thanks to the egg of hundred years, we know how to remove a shell now without tiring us. It is sufficient to attack it to vinegar!

The ideal white

To give the best taste to the white is simple: it is sufficient to put salt in the water, because salt distributes itself throughout the egg, by holes of the shell. Do you want a proof of the existence of these holes? Observe an egg in boiling water: you will see small bubbles.

So salt will flavor the white, but how does one make it soft and non rubbery? This time, a little organic chemistry is necessary. The white of egg comprises 90 percent water and 10 percent proteins. Now, water molecules are shaped like the head of Mickey Mouse, with a big atom of oxygen for the head and two atoms of hydrogen for the ears. Dispersed at the middle of the white, the molecules of the proteins are bigger. They are not shaped like a Mickey Mouse head, but instead are shaped like necklaces of pearls folded on themselves, with, at the center, the parts that don't dissolve themselves well in water, and, especially, the sulfur atoms. When one heats this white of egg, the protein molecules jopin to each other by their sulfur atoms. This forms a net that traps the water molecules. What is more important for our subject, it is that more one heats, the more the net tightens himself and more water escapes, as when one presses a sponge. In other words, a white of egg when overcooked becomes hard. When does this annoyance occur? At about 1200 F, the temperature at which the white begins to thicken. At 2120 F, or boiling, to which one usually cooks eggs, the tenderness disappears quickly.

Thus, to have a tender white, it is necessary to cook the egg to the possible lowest temperature 1200F, but don't forget to cook longer than the classic 10 minutes at 2120 F. Doesn't the longer cooking time make the yolke turn turn green? No, because the temperature saves the proteins, instead of damaging them. With a soft cooking, the protein molecules don't lose by their sulfur atoms, so the sulfur atoms don't form sulphurized hydrogen, this sickening gas that comes to turns the yolk green.

The ideal yolk

Now, how does one make a yolk that is not gritty in texture? The principle is the same that for the cooking of the white: it is necessary to cook to as low temperature that possible. Boiling is excessive. How far we can descend? If we cook at only 1200 F, the white will cook, but not the yolk, because the temperature of minimal coagulation of the yolk is of about 1300 F. Consequence: to cook all the egg, white and yolk, we should put the egg in salted water salted at a temperature near to 1300 F.

How do we center the yolk in the white? Let's examine what of it says the classic kitchen. Mrs. Saint Angel, for example, writes (in The Good Kitchen of Mrs. Saint Angel, Larousse editions) that the eggs must be put in the boiling water so that the yolks are well at the center.

Augustus Colombii indicates: "If we put the eggs in the cold water, another phenomenon would take place. The yellow weighs more that the white, the heat reaches this one more quickly since it is outside, and the lighter again; the yellow falls again on the shell and on one hand, you see the egg then being cooked, a big layer of white on one hand and, of the other, the yellow to show on the surface to the outside."

Why would the yellow weigh more that the white? Let's start with weighing a yellow and a white: it is, in fact,the inverse that we learn. So did Augustus Colombii want to speak of density, rather than of weight? Let's consider an egg, whole, in its shell. Where is the yellow? Does it float in the white or, as Augustus Colombii indicates it, does it descend toward the shell?

Take one second to think about the question. The majority of people questioned about the relative density of the yellow and the white answer, as Augustus Colombii, that the yellow must be denser than the white. Yet the simple experience that consists in placing a yellow in a test-tube, then to add four whites over it, reveals to the contrary that the yellow is less dense: it rises slowly in the whites. Inversely, if one places it in surface, above the whites, it remains there.

The reason for the difference in density: the yellow contains some lipids (oils), whereas the white is nearly all water. If you are not convinced, cook a standing egg, and you will see the yellow on the top. Or, as I asked my brother the radiologist to do, make an X-ray of an egg, and you will see the yellow well in the top of the white. Or put a cool, raw egg, in vinegar and wait until the day that the shell is nearly transparent to see the yellow floating in the white! From where the unassailable conclusion: when you cook an egg without moving it, the yellow floats in the shell, and it will be decentered. How to center it, then? Roll the egg in the pan, with the help of a wooden spoon, and there won't be a top anymore; after cooking, the yellow will be centered in the white.

And this is how the hard-boiled egg will be perfected!