Are cooks technicians or technologists? Les cuisiniers sont ils des techniciens ou des technologues ?

 Pour la réponse en français, voir : https://scilogs.fr/vivelaconnaissance/cuisinier-technicien-ou-technologue-ou-artiste/

 

And now in English

 

An important observation is to recognize that doing something (techne) is a technical work, whereas trying to improve the technique is technology. 

Also, art had many definitions, but it has something to do with emotions. 

And this preliminary  observations can be summarized with : 

Rembrandt was an artist

A wall painter is a technician. 

 

With this in hands, it should be clar that, for cooks : 

-  some of them are craftpersons, as they do technique primarily (the repeat protocols, they do not innovate really) ; mind that, in this category, you have the "art craftperson", repeating but with more emphasis on beauty than others)

- some of them are artists (their dishes are for the mind, not the body)

Now, cooks who would try to improve the culinary technique would be technologists, but if a person is spending his/her time at improving culinary techniques, he/she is a technologist... and no longer a cook.

All this is discussed in my books :

1. Cooking, a quintessential art

2. Cours de gastronomie moléculaire N°1 : science, technologique techniques culinaires.

 

Questions about custard/ Questions à propos de crème anglaise

Pour la version en français : 

https://scilogs.fr/vivelaconnaissance/on-minterroge-a-propos-de-creme-anglaise/

 

This afternoon, a salvo of questions which are, in fact, all about cooking custards.
I have illustrated and (I hope) clear and detailed explanations in Mon histoire de cuisine (Belin, Paris), but here is something to understand.





The message:

I know that white starts to coagulate at 62°C, yellow at 68°C (I read your article on Pierre Gagnaire's website), but I think that some molecules coagulate at other temperatures; am I wrong?
A related question: why does it say to cook the custard at 85°C? Could it be for pasteurisation purposes? And why does it slice at boiling point and not at 85°C?
Is it possible to catch up with a turned custard to regain the emulsion? Will this have any effect on the molecular structure or texture?
I observed that the custard was more liquid after being "blended". Is this a destruction of the molecular structure during blending?



And my answer, question by question


Here, let's start with :

I know that the white starts to coagulate at 62°C, the yellow at 68°C (I read your article on Pierre Gagnaire's website), but I think that some molecules coagulate at other temperatures; am I wrong?


One can of course answer point by point to this first question, and I will do so, but I will also take it up differently, because I think one can be clearer.

First, the poor answer, point by point:
Yes, the egg white starts to coagulate at around 62°C.
Yes, egg yolk starts to coagulate at around 68°C.
And yes, some egg molecules coagulate at temperatures other than the two above.
But first I observe that the molecules that coagulate, in the white or in the yolk, are more precisely proteins. Each protein, each kind of protein-like molecule) coagulates at a particular temperature.

Now, as I said before, I know that the answer is not correctly given, that the explanation is not clear, so I'll take it up now.

Let's consider the egg white, since the yolk behaves in principle like it, but in a slightly more complicated way.
The egg white is 90% water and 10% protein, but several kinds of protein.
Each protein coagulates at a particular temperature.
And it is indeed at 61.8°C that the first protein in the white coagulates; the others remain in the form of balls in the white, barely caught by the coagulation of this first coagulating protein (we agree: when we say "a protein coagulates", it means that many molecules of the same type of protein "uncoil" and form a large network that traps the liquid in which they were dissolved).
Then, when the temperature is increased, a second protein coagulates, which reinforces the gel that is the coagulated blank. At this stage, there are two "nets" which trap the other molecules, and it is very soft.
And when the temperature is increased further, a third protein coagulates, reinforcing the gel that is the coagulated white, then a fourth coagulation will come, and so on, the coagulated white becoming harder and harder, until it becomes rubbery.

The same applies to the egg yolk, but with different proteins, which have different coagulation temperatures.


The rest almost follows from this


A related question: why do we say to cook custard at 85°C? Could it be for pasteurisation purposes? And why does it boil and not boil at 85°C?

First of all, let's observe that you can cook custard at any temperature you want, and I don't know where my interlocutor is getting it from: 85°C.
I am not a specialist in microbiological issues, but I know that there is above all the question of the "time-temperature couple". For example, if you cook a whole egg, in its shell, at 59°C for 15 minutes, you destroy salmonella; when you cook at a temperature higher than 59°C, you can reduce the time needed for microbiological sanitation. On the other hand, care must be taken not to go too low, because when micro-organisms are at a high but not lethal temperature, they proliferate.
This is why I so often warn my cooking friends against keeping temperatures too low for a long time.

That said, yes, you can make a custard froth when you bring it to high temperature... For a reason that I will now explain, by saying first of all that a custard that is macroscopically successful, i.e. visible to the naked eye, is actually microscopically frothy.
And I would add that, contrary to what has often been wrongly taught, a custard is not an emulsion but a suspension: it is not like in a mayonnaise, where the stacking

See also : 

Le diable est tapi dans les laboratoires

1. Introduction

Je sais bien que des amis m'ont dit qu'il ne fallait pas dire "C'est simple", à des étudiants, mais :
1. je crois que ce conseil est mauvais
2. j'ai analysé ma position et je l'ai publiée
3. je crois que, si c'est un encouragement, alors c'est utile
4. quand on avance pas à pas, le plus long des chemins n'est qu'une succession de pas (qui veut voyager loin ménage sa monture, en quelque sorte).

Voir :

https://seafile.agroparistech.fr/f/f32e0e619cf340eaabbe/?dl=1

 

En l'occurrence, je propose de voir, avec un nouveau texte, qu'un mélange de calculs simples, formel et numérique, permet d'analyser des cas analytiques pathologiques (en rappelant qu'analyse et synthèse sont indissociables, en chimie et en physico-chimie.


2. La question posée : l'intégration des signaux

Le texte complet est téléchargeable ici :

https://seafile.agroparistech.fr/f/45c58d531d69407aa33d/?dl=1

In English: Atoms, elements, compounds, substances...

It's a mess.
In the Encyclopedia britannica (https://www.britannica.com/science/chemical-compound), I looked for the definition of "chemical compound", and I found a very messy and wrong text.
Indeed, here it is: "chemical compound, any substance composed of identical molecules consisting of atoms of two or more chemical elements".

And immediately, you see the mistake, as a "substance" is a material object: water is a liquid substance, in the ambiant conditions, and iron is a solid substance, with metallic aspect. But water (the substance) is made of identical objects, i.e., molecules ("water molecules"), which are made of atoms of different kinds, such as hydrogen (the element, not to be confused with dihydrogen) or oxygen. And "water" is also the name of the compound "water", i.e. the chemical category of all molecules made of one oxygen atom and two hydrogen atoms.

For sure, the fact that "water" applies to a substance  and a compound creates confusion. Moreover, the word "water" applies to the chemical pure water (substance) as any tap water, or water in the river, or sea water, which are rather aqueous solutions containing a lot of solutes, such as ions, molecules, etc.

Let's read more: "All the matter in the universe is composed of the atoms of more than 100 different chemical elements, which are found both in pure form and combined in chemical compounds."
Yes, no, the matter of the universe is not composed of the atoms of etc."... because there are a lot of subatomic particles, not considering dark matter.

More : " A sample of any given pure element is composed only of the atoms characteristic of that element, and the atoms of each element are unique". No, again : a "pure element" does not exist : an element is an element, a category of atoms, and the question of purity has no meaning here. Purity can only apply to substances, to materials.
And no again, the atoms of an element are not all the same, because some can have more neutrons than others. Wrong again: don't you think it's too much?

More :
"For example, the atoms that constitute carbon are different from those that make up iron, which are in turn different from those of gold." : here, the mistake in the "make up". Stricto sensu, objects don't "make up" a category.

" Every element is designated by a unique symbol consisting of one, two, or three letters arising from either the current element name or its original (often Latin) name." : yes.

"For example, the symbols for carbon, hydrogen, and oxygen are simply C, H, and O, respectively. The symbol for iron is Fe, from its original Latin name ferrum.  : yes.

" The fundamental principle of the science of chemistry is that the atoms of different elements can combine with one another to form chemical compounds." : here, there is a pleonasm, was chemistry being a science, expressions such as "the science of chemistry" is too much.

And here, I have enough, but shouldn't EB make corrections?