Le contenu du livre de Jane Marcet, qui inspira Michael Faraday

 Le contenu du livre de Jane Marcet, qui inspira Michael Faraday

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CONVERSATIONS ON CHEMISTRY
IN WHICH THE ELEMENTS OF THAT SCIENCE ARE FAMILIARLY EXPLAINED AND ILLUSTRATED
BY EXPERIMENTS; IN TWO VOLUMES.
VOL. I: ON SIMPLE BODIES
BY JANE MARCET
Contents of the First Volume on Simple Bodies
CONVERSATION I.
On the General Principles of Chemistry..............................................................................
Connection between Chemistry and Natural Philosophy.
Improved State of modem Chemistry.
Its Use in the Arts.
The general Objects of Chemistry.
Definition of Elementary Bodies.
Definition of Decomposition.
Integrant and Constituent Particles.
Distinction between Simple and Compound Bodies.
Classification of Simple Bodies.
Of Chemical Affinity, or Attraction of Composition.
Examples of Composition and Decomposition.
CONVERSATION II.
On Light and Heat...........................................................................................................................
Light and Heat capable of being separated.
Dr. Herschel’s Experiments.
Phosphorescence.
Of Caloric.
Its two Modifications.
Free Caloric.
Of the three different States of Bodies, solid, fluid, and aeriform.
Dilatation of Solid Bodies.
Pyrometer.
Dilatation of Fluids.
Thermometer.
Dilatation of Elastic Fluids.
Air Thermometer.
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2
Equal Diffusion of Caloric.
Cold a negative Quality.
Professor Prevost's Theory of the Radiation of Heat.
Professor Pictet's Experiments on the Reflection of Heat.
Mr. Leslie’s Experiments on the Radiation of Heat.
CONVERSATION III.
Continuation of the Subject..........................................................................................................
Of the difierent Power of Bodies to conduct Heat.
Attempt to account for this Power.
Count Rumford's Opinion respecting the non-conducting Power of Fluids.
Phenomena of Boiling.
Of Solution in general.
Solvent Power of Water.
Difference between Solution and Mixture.
Solvent Power of Caloric— Of Clouds, Rain.
Dr. Wlls' Theory of Dew, Evaporation, &c.
Influence of Atmospherical Pressure on Evaporation.
Ignition.
CONVERSATION IV.
On Combined Caloric, Comprehending Specific and Latent Heat..........................................
Of Specific Heat.
Of the different Capacities of Bodies for Heat.
Specific Heat, not perceptible by the Senses.
How to be ascertained.
Of latent Heat.
Distinction between Latent and Specific Heat.
Phenomena attending the Melting of Ice and the Formation of Vapour.
Phenomena attending the Formation of Ice, and the Condensation of Elastic Fluids.
Instances of Condensation, and consequent Disengagement of Heat, produced by
Mixtures, by the slaking of Lime.
General Remarks on Latent Heat.
Explanation of the Phenomena of Ether boiling, and Water freezing, at the same
Temperature.
Of the Production of Cold by Evaporation.
Calorimeter.
Meteorological Remarks.
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CONVERSATION V.
On the Steam-Engine......................................................................................................................
Origin of the Steam-Engine.
Marquis of Worcester's Invention.
Savary and Newcomen's Engine.
Watt's Double Steam-Engine described.
Wolff's Engine.
Advantages derived from the Steam-Engine.
CONVERSATION VI.
On the Chemical Agencies of Electricity......................................................................................
Electricity, positive and negative.
Galvani's Discoveries.
Galvanism.
Voltaic Battery.
Electrical Machine.
Theory of Voltaic Excitement.
Its Influence on the Magnetic Needle.
CONVERSATION VII.
On Oxygen and Nitrogen...............................................................................................................
The Atmosphere composed of Oxygen and Nitrogen in the State of Gas.
Definition of Gas.
Mr. Faraday's Experiments on the Liquefaction and Solidification of Gases.
Oxygen essential to Combustion and Respiration.
Decomposition of the Atmosphere by Combustion.
Nitrogen Gas obtained by this Process.
Of Oxygenation in general.
Of the Oxidation of Metals.
Oxygen Gas obtained from Oxide of Manganese.
Description of a Water-bath for collecting and preserving Gases.
Combustion of Iron Wire in Oxygen Gas.
Fixed and volatile Products of Combustion.
Patent Lamps.
Decomposition of the Atmosphere.
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CONVERSATION VIII.
On Hydrogen....................................................................................................................................
Of Hydrogen.
Of the Formation of Water by the Combustion of Hydrogen.
Of the Decomposition of Water.
Detonation of Hydrogen Gas.
Description of Lavoisier's Apparatus for the Formation of Water.
Hydrogen Gas essential to the Production of Flame.
Musical Tones produced by the Combustion of Hydrogen Gas within a Glass Tube.
Combustion of Candles explained.
Gas Lights.
Detonation of Hydrogen in Soap Bubbles.
Air Balloons.
Meteorological Phenomena ascribed to Hydrogen Gas.
Miner's Lamp.
CONVERSATION IX.
On Sulpher and Phosphorus..........................................................................................................
Natural History of Sulphur.
Sublimation.
Alembic.
Combustion of Sulphur in Atmospheric Air.
Of Acidification in general.
Nomenclature of the Acids.
Combustion of Sulphur in Oxygen Gas.
Sulphuric Acid.
Sulphurous Acid.
Decomposition of Sulphur.
Sulphuretted Hydrogen Gras.
Harrowgate, or Hydro-Sulphuretted Waters.
Phosphorus.
Decomposition of Phosphorus.
History of its Discovery.
Its Combustion in Oxygen Gas.
Phosphoric Acid.
Phosphorous Acid.
Eudiometer.
Combination of Phosphorus with Sulphur.
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5
Phosphoretted Hydrogen Gas.
Nomenclature of Binary Compounds.
Phosphoret of Lime burning under Water.
CONVERSATION X.
On Carbon........................................................................................................................................
Method of obtaining pure Charcoal.
Method of making common Charcoal.
Pure Carbon not to be obtained by Art.
Diamond.
Properties of Carbon.
Combustion of Carbon.
Production of Carbonic Acid Gas.
Carbon susceptible of only one Degree of Acidification.
Gaseous Oxide of Carbon.
Of Seltzer Water, and other Mineral Waters.
Effervescence.
Decomposition of Water by Carbon.
Mr. Bunsen's Experiments to produce Light at a cheap Rate.
Carburet of Iron.
Oils.
Vegetable Acids.
Of the Power of Carbon to revive Metals.
CONVERSATION XI.
On Metals.........................................................................................................................................
Natural History of Metals.
Of Roasting, Smelting, &c.
Oxidation of Metals by the Atmosphere.
Change of Colours produced by different Degrees of Oxidation.
Combustion of Metals.
Perfect Metals burnt by Electricity only.
Some Metals revived by Carbon and other Combustibles.
Perfect Metals revived by Heat alone.
Of the Oxidation of certain Metals by the Decomposition of Water.
Power of Acids to promote this Effect.
Oxidation of Metals by Acids.
Metallic Neutral Salts.
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Previous Oxidation of the Metal requisite.
Crystallisation.
Solution distinguished from Dissolution.
Five Metals susceptible of Acidification.
Meteoric Stones.
Alloys, Soldering, Plating, Gilding, new Mode by Electricity.
Of Arsenic, and of the caustic Effects of Oxygen.
Of Verdigris, Sympathetic Ink, &c.
Of the new Metals discovered by Sir H. Davy, by means of Electricity.

The translation in English of a text that I published first in French, about the rigor in the use of words of chemistry

Rigourous terminology for concepts of chemistry: a base for rational choices.

Hervé This 1



1 INRAE, UMR 0782 SayFood, France.
 Correspondance :
Intae-AgroParisTech International Centre for Molecular and Physical Gastronomy
herve.this@inrae.fr

Translated from  This H. 2021. La rigueur terminologique pour les  concepts de la chimie : une base pour des choix de société rationnels, Notes Académiques de l'Académie d'agriculture de France / Academic Notes from the French Academy of Agriculture, 2021, 1, 1-15.




Abstract
Food-related decisions that engage communities are often based on chemical concepts. Therefore, the utmost terminological rigour is required. This article considers frequent examples of confusion, and concludes with a call for the introduction of chemistry lessons as early as primary school.


Keywords
chemistry, human food, public debate, controversies, terminological rigor, molecule, compound, fatty acid, triglyceride, minerals, natural product, chemical denomination





Introduction

Public debates about food often involve chemical objects: nitrates, nitrites (Pouliquen, 2020), fatty acids (INSERM, 2020), glyphosate (Foodwatch, 2020), acrylamide (Cérou, 2020), iron (Santé Magazine, 2020), curcumin (Lacamp, 2020), DNA (Bru, 2020), mineral salts (Mary, 2020), pesticides (Foodwatch, 2020), micro-plastics (Anses, 2020a), nano-particles (Anses, 2020b)... Unfortunately, some of those who intervene in these debates are ignorant of the exact nature of these compounds and products, or have negative perceptions of them, as the consultation of the references given above shows over and over again! In particular, the belief in a "good nature" - which forgets for example natural poisons such as hemlock or datura - is not new (Mill, 1874), but it continues to rage, while unfounded fears are heard (Kressmann, 2018).
The bad knowledge of the objects of chemistry is deleterious, in the public debates where these objects intervene, because it can lead to irrational positions and choices of the public and the elected officials, then to laws which risk to govern the collective life in an unacceptable way for whoever seeks more rationality and a better use of the public money (Vaulpré et Jaffré, 2020). Already Nicolas de Condorcet wrote, at a time when science was considered as a "natural philosophy": "Any society which is not enlightened by philosophers is deceived by charlatans". (Condorcet, 1791).
It is true that chemistry courses have been introduced in secondary school courses, but they are limited, and recent surveys show the weakness of France, from this point of view (Cabioch, 2020), compared to other countries in the world. Beyond questions of national industrial competitiveness, training in chemistry is essential for citizens to be able to make up their minds in the highly technical world in which they live today. As young people become adults, and eventually elected officials, Parliament has deemed it essential to strengthen the scientific and technological knowledge of elected officials through the Parliamentary Office for the Evaluation of Scientific and Technological Choices, created in the early 1980s (OPECST, 2020): scientific information and training (especially in chemistry) help to avoid erroneous ideas, either resulting from personal preconceptions or propagated by pressure groups... And the issue of insufficient knowledge of science, especially chemistry, is serious enough that it is frequently considered by states and international organizations, including UNESCO, which has been concerned with the popularization of natural sciences in the public service media (Naji, 2006).
In this article, we analyze a series of frequent confusions, with a view to discussing further the reasons why rigorous terminology is needed, especially for the objects of chemistry. We address readers who are trained in the natural sciences, but not all of them chemists, and we also examine presentations to citizens who are not always well educated in science, seeking to show why those who are in a position to abuse language might usefully avoid it in public debate.
We wish to establish that rigor is never excessive when discussing questions that involve chemical objects, at the risk of confusions that would make the bed of ideologues or dishonest people, or that would lead to the unreasoned fears that we have mentioned.


An anthology, before taking a step back
 
1. A first common error, in relation to chemistry, is the abuse of language that consists in speaking of "molecules" to refer to "chemical species", in particular  "compounds" (Myers, 2012). Chemistry hesitated for a long time, before considering -at last- that a molecule is an assembly of atoms, whereas a compound is a category of molecules that are all identical, a particular kind of "chemical species" for which there are atoms of more than one chemical element. To say that water is a molecule, for example, must be avoided, because it is false, in the modern sense of the word "molecule". For the public, water is a liquid, and for chemistry, water is a material, a  "substance" which can be in the vapor phase, or liquid, or solid, for example, depending on temperature and pressure conditions (Lide, 2005); generally, for the samples considered on Earth, this material is made of very many identical molecules: tens of thousands of billions of identical molecules per gram of water (IUPAC, 2004).
A detail that is useless for citizens trained in the natural sciences, but essential for all those who do not have sufficient training and who participate in public debates: each of the water molecules is made of one oxygen atom and two hydrogen atoms, which is conventionally noted H2O (Lower, 2020). Water is a "compound" (since its molecules are made of atoms of two different chemical elements: oxygen and hydrogen).
Finally, above we have made the assumption of an absolute purity of the samples, but we will see later (example 5) that it is interesting to distinguish this pure water (rare on the Earth), made only of water molecules, from the water we drink, which inevitably contains a number of "impurities", i.e. molecules which are not water molecules, or various ions (sodium, magnesium, chloride, nitrate, etc.).
What is said about water obviously applies to other compounds.
In any case, the abuse (or impropriety, depending on the case) of language which consists in speaking of "molecule" to evoke a chemical species has serious consequences: the author of this text can testify to having met a science journalist from a public service television channel who thought (and explained to his audience!) that there were 450 odorant molecules in wines, and this person was thinking of 450 particular objects, of 450 molecules of chemists, and not of 450 odorant compounds (chemical species). Because yes, wine contains a few hundreds of different odorant compounds (depending on the wine), but each of these compounds is present, in a bottle of wine, at a rate of hundreds of thousands of billions of molecules (Pons et al., 2017).
The practice of popularization conferences, as well as the questioning of passers-by in the street, show that this case was very far from being isolated: when the notion of molecules is declared to be known, the idea to which it corresponds is very often erroneous, without even going so far as to hope that the citizens know that the molecules of a liquid are all in movement.
Let us add that the confusions between "compounds" and "molecules"(or  "chemical species"), when they are not abuses of language, can result as much from insufficient knowledge of chemistry, notably of its vocabulary, as from the difficulty of thinking about categories, already discussed by Aristotle, then many others (Van Aubel, 1963), before being, for example, one of the pitfalls of teaching, notably that of "modern mathematics" (Thom, 1970).
This is one reason why the introduction of the modern notion of molecules was such a remarkable achievement of chemistry, due in particular to Amedeo Avogadro (1776-1856), that it remained the object of violent scientific controversy until the first half of the twentieth century: French chemists, notably around Marcellin Berthelot, refused the modern (yet correct) idea of molecule, and their political influence, notably in terms of education and university training, caused French chemistry to lag half a century behind (Jacques, 1987).
In short, there are many reasons to be vigilant about this word "molecule", especially when one is addressing interlocutors or a public who are not aware of the possibilities of confusion.

2. More specifically, abuses of language that I believe to be harmful, in food science, technology, and engineering, are to speak of "fatty acids in a triglyceride" or "amino acids in a protein": it is more accurate (and internationally decided) to use the terminologies "fatty acid residues" and "amino acid residues", respectively, for the parts rightly designated as such, in triglycerides or in proteins (IUPAC, 2019).
Why? Because free fatty acids, for example (we are sometimes obliged to add the adjective "free" to make ourselves clear), are quite different compounds from triglycerides. And, often, it is useful to add that there are almost no (free) fatty acids in oils or in other food fats: it was, this time, a contribution of the French chemist Michel-Eugène Chevreul (Angers, 1786 - Paris, 1889) to establish that food fats are mostly composed of "triglycerides", and not fatty acids, recognizing by measurements of great precision (at that time) that the esterification reaction by which we can eventually synthesize a triglyceride does not correspond to a juxtaposition, but a real reaction, which changes the nature of the reactants (Chevreul, 1823). In the case of proteins, it was not until Theodor Svedberg's advances in the 1920s that the difference between a polymer (which proteins are) and a colloidal assembly (of amino acids, in this case) was finally understood (Florkin and Stotz, 1972).
The experience of university teaching shows how widespread is the confusion between fatty acids and triglycerides, or amino acids and proteins; it remains often until the master's degree, and, similarly, the analysis of public discussions shows how confused ideas are often on this subject.
In order to explain things to a public that constantly hears about "the fatty acids of table oils", even in food hygiene documents (PNNS, 2020; Olivier et al., 2014), we can usefully begin by pointing out that oil (like most food fats) is mainly made up of a large number of molecules similar to octopuses with three flexible arms: these molecules are "triglycerides". Note that we could also say "triacylglycerols", but this would unnecessarily increase the complexity (Figures 1 and 2).
Oils, for example, contain other compounds than triglycerides, but they are very much in the minority. For example, in the middle of the triglyceride molecules, oils also contain fatty acid molecules (free, therefore), squalene molecules, terpene acid molecules, sterol molecules, etc., but the total of all these, constituting the oil, is only one percent by mass.
Let's concentrate on these triglycerides which are in the majority. Oil and other fats contain a large number of different triglycerides (several billion for milk fat), the names of which are set by the international rules of the International Union of Pure and Applied Chemistry (IUPAC, 2019): the general rules of chemical naming lead to the recognition, in the center of triglyceride molecules, of a unit of three linked carbon atoms, each one linked to an oxygen atom, which is also the case in the molecules of the compound named glycerol (Figure 3). However, there is no glycerol (the compound) in the molecules of triglycerides; there is only a group of atoms reminiscent of glycerol, by the way, to within three hydrogen atoms (which is no small thing, in chemistry), and so one must speak, for this part identified by thought of "glycerol residue" (IUPAC, 2019).
Starting from this center, which is the  "glycerol residue", after the oxygen atoms that have been mentioned for this residue, the triglyceride molecules carry long chains of atoms that differ little from those of molecules of compounds that would be fatty acids: fatty acid molecules are, in fact, chains of carbon atoms bonded exclusively to hydrogen atoms, with, at one end, a "carboxylic acid" group, the terminal carbon atom being bonded to an oxygen atom by a double bond, and to a hydroxyl group, made of an oxygen atom itself bonded to a hydrogen atom (Figure 4). In triglycerides, this structure is not present as such, but only discernible to a few atoms. One can only recognize, in triglyceride molecules, a glycerol residue and three "fatty acid residues".
Why would some people (chemists or not) hesitate to say the right things? Why would they refuse to be terminologically rigorous? Because triglycerides could be assembled from fatty acids, and degraded to fatty acids? In reality, triglycerides can be constituted and modified in many different ways, and not necessarily by assembling one glycerol molecule and three fatty acid molecules. It depends on the reaction conditions: reagents present, pH, presence of free radicals, catalysts, etc.
Above all, to speak improperly of fatty acids (instead of "fatty acid residues") in fats is to expose oneself to the risk that the public (and even students of food science, technology and engineering) will think that oil is made of fatty acids! The risk even concerns people trained in science: the author of this text testifies that he knows an excellent physicist, a distinguished research director in his discipline, who believed this... because the confusing ambient language made him think so.
A nutritionist colleague who spoke of "triglyceride fatty acids" was questioned in the preparation of this article, and his reasons included (1) habit and (2) the fact that the public might fear "residues"... The first reason is not sufficient, as the history of chemistry has shown, which has progressed with the clarification of terminology, but the second is debatable: is there not a risk of paternalism in believing that the public is incapable of thinking well (This and Panel, 2010), knowing moreover how many charlatans, dishonest people, and ideologues sneak into the slightest intellectual breach to propagate their pernicious ideas?
And then, if the word -accepted inter-nationally- of "residue" seems difficult to use, why not use "fragment", or "group", for example... knowing that, in French, a residue is a part that remains after a main part has been removed, for example by evaporation: the connotation is not necessarily negative.

3. A third example, concerning "mineral salts", is intended to show the extent to which abuses of language can insidiously induce false ideas, even in scientific circles. We will begin by observing that, very often, the expression "mineral salts" should be replaced by "mineral ions", or "the mineral content of... ".
Let's start by observing that we often hear and read that water contains "mineral salts", or worse, that "calcium" and other mineral ions would be mineral salts (Passport to Health, 2020; Greenfield and Southgate, 2007)... This is incorrect for several reasons. First, calcium is an "element" and is only present in foods as divalent calcium ions. Secondly, a mineral ion, such as the calcium ion, is not a mineral salt, but only a mineral ion, which could be a constituent of a mineral salt if it were in a crystalline structure, with ions of opposite charge (at least in balance). Finally, "mineral salts" are (under ambient conditions) crystallized solids, such as sodium chloride (of which our table salt is mostly composed).
If we place crystals of a salt (for example, sodium chloride) in water, the constituent ions (chloride and sodium) can disperse, surrounding themselves with water molecules, and a solution of this salt can be formed (within the limits of solubility). In this particular case of the dissolution of a single salt, the water does contain a mineral salt, in solution, as long as it has been put in.
However, this is no longer true for ordinary drinking water, which contains various mineral ions: sodium, potassium, magnesium, chlorides, nitrates, sulphates, phosphates... These waters do indeed contain mineral ions, and they therefore have a mineral content, but do they contain mineral salts?
It is with regard to the last question that the difficulty arises, as can be seen from the simple case of an aqueous solution in which two mineral salts, such as sodium chloride and potassium nitrate, for example, have been initially dissolved. This solution would be the same if potassium chloride and sodium nitrate had been dissolved instead, so that, without knowing how the solution was constituted, it is impossible to say which mineral salts it may contain.
More generally, when faced with a solution that has a mineral content, it is impossible to say what "mineral salts" it contains. What is true for an aqueous solution is true for food ingredients and foods, including plant or animal tissues, or culinary preparations made from them: all have a mineral content, all contain mineral ions, but it would be very difficult to identify the mineral salts they contain. Conclusion: food does not contain mineral salts!
 
4. The fourth example concerns a more subtle - but chemically essential - characteristic of food compounds: their "chirality". To discuss this, let us first recall a tragic episode in pharmacy.
In the 1950s and 1960s, thalidomide was prescribed to pregnant women to relieve morning sickness, but it was overlooked that the compound appears in two mirror-image forms, like a left hand and a right hand. Just as a left hand is not a right hand, a left molecular form has different chemical and biological properties than a right molecular form (Figure 5). Metaphorically, one does not fit the left hand into the right glove or vice versa, and what applies to hands and gloves applies to active ingredients and biological receptors (Jacques, 1981). In the case of thalidomide, its "right" chiral form relieves nausea, while its "left" form causes malformations in the fetus: 10,000 to 20,000 children were born in this way, terribly affected, because of the confusion!
With foods, whether nutrients or bioactive compounds, the same question arises, and so chirality (the left-hand/right-hand difference) has become the daily tool of flavourists and perfumers: for example, (+)-(S)-carvone and (-)-(R)-carvone do not smell the same, like spearmint or dill. Or, (E)-anethole (trans form) is very low in toxicity, while the cis form, synthetic or natural trace, is much more toxic. Both enantiomers of linalool are natural, but while the (+)-(S)-linalol in coriander is very low in toxicity, the (-)-(R)-linalol in basil and lavender is higher. To simply talk about "anethole", for example, is simplistic... not to mention the disasters it can cause!

5. From compounds, let us now turn to "products" used in food. For the former, we have mentioned the common difficulty of thinking in terms of categories, but we have not gone into the details of the philosophical difficulties, namely that "the horse" is a very heterogeneous category: ponies, percherons, bay horses, grey horses, piebalds... This question is encountered with food ingredients.
Here again, public debates are hasty: "the" flour, for example... Which flour? What kind? With what composition? Bakers and confectioners are well aware of the variability of this product, even when only wheat flour is considered, to the point that it complicates recipes considerably (Inbp, 1990): the amount of water that must be added to a dough depends on the year, the origin, the grinding, the temperature of use... This same type of observation is valid for most of the food ingredients: "gelatine", "lecithin", etc.
Here for "products" as about the chirality of compounds, the question is terminological, and the consequences are sometimes serious. We recall the terrible episode of 2019, when a pharmaceutical company changed the formulation of its drug against hypothyroidism: the change in formulation, which was not accompanied by a change in name, had terrible consequences for many patients who used "the" product (Ansm, 2017). For food, this issue must be analyzed in the light of the 1905 law on the food trade, which must be "fair" (horse is not beef): this fairness requires fair designations (French Academy of Agriculture, 2011) and, in particular, fair chemical designations. Hence the importance of IUPAC, mentioned earlier.
This observation finds its full importance in relation to food additives: there is certainly a need for better designation (Anses, 2016). For example, the additive designated by the European code E140 corresponds to what is sometimes called chlorophyllin, or sometimes chlorophyll (Efsa, 2015), but, ultimately, what is it?
Let us first observe that "the" chlorophyll is an outdated terminology, introduced in 1818 by the French pharmacists Joseph Bienaimé Caventou (1795-1877) and Pierre Joseph Pelletier (1788-1842) to designate what cooks called "spinach green" (This, 2019); today, we know "chlorophylls", with different light absorptions: a, a', b, b', c, d, e, etc. On the other hand, the preparations made from chlorophylls and metals, such as zinc or copper, are no longer chlorophylls (in the center of which there is naturally a divalent magnesium ion), but chlorophyllines, zinciques or cuivriques, for example.
Similarly, we find the question about "lecithin" (IUPAC, 1979), a term that still suffers from the hesitations of chemistry, when it was young and more imperfect than today. Here, the story begins in 1845, when the French chemist and pharmacist Theodore Gobley isolated "lecithin" from egg yolk (lekithos means "egg yolk" in Greek); in 1874, he established the complete chemical formula of "lecithin phosphatidylcholine" (Gobley, 1874). Between 1850 and 1874, he had demonstrated the presence of "lecithin" in a variety of biological materials, including venous blood, human lungs, bile, human brain tissue, fish eggs, and chicken and sheep brains.
How to admit that, today, "lecithin" designates preparations (mixtures of compounds, therefore), with different properties according to the producers? The differences in functionality of the various preparations expose users to problems. Of course, one could say that no material is constant: "gelatin" can have a lot or little gelling power, depending on the batch; the same goes for "pectin", of which there are various varieties... even for "egg white powder", which is sold under this name, whether it is cooked and dehydrated egg white or fresh dehydrated egg white, with considerable differences in functionality for the two products (one does not coagulate, and the other can coagulate). Wouldn't it be in our interest, in the interest of fair trade, to better designate the food ingredients that are traded?

6. The same question is found with the products called - unfortunately - "flavors" (Dgccrf, 2006), and for which I propose to analyze that the terminological vagueness has undermined social cohesion. Indeed, we all know that, on the one hand, these products are widely used by the food industry, and, on the other hand, they are widely criticized - for a long time - by a part of the population (60 Millions de consommateurs, 2016). Could it not be interpreted that the public fears deception? In fact, the food industry and regulatory authorities have warped the word "aroma", which in French means the smell of an aromatic plant, an aromatic (TLFi, 2020). It would have been wiser not to use this term to designate flavoring compositions or extracts!
Because that is what it is all about: these compositions or extracts (which are never "natural", stricto sensu, since they are produced by craftsmen or industrialists) are either "compositions", obtained by mixing odorant compounds, by a technical and artistic work which is similar to that of the perfumer ; or "extracts", obtained by methods that resemble the production of table sugar from beet, or the production of eaux-de-vie from wines, with, in this case, processes that range from cold pressing to distillation, possibly with solvents (Sniaa, 2020). Since the public is right to think that compositions or extracts are not "flavors", in the sense of the common language, but rather flavoring agents, wouldn't the food industry, if it wants to show its loyalty, and the regulatory authorities, if they aim for more social cohesion, have an interest in taking the measure of the error initially made and changing the terminology?
Let us add two points:  (1) the English language distinguishes flavour from flavourings; (2) some of these flavourings are so remarkable, from an olfactory point of view, that there is hardly any reason not to make them available to the public, so that they can use them in their daily cooking... provided that they have a correct perception of them.

7. In the previous paragraph, we sketched out a discussion of the term "natural", but we did not insist enough to point out that the regulations also contradict the dictionary when they accept this adjective for products, flavourings (Sniaa, 2020) or others. Insofar as naturalness excludes the intervention of a human being (TLFi, 2020b), this use of the term "natural" is unwarranted, even dishonest: the "products" have indeed been produced, by human beings, so that they are strictly speaking "artificial".
If one were too lax, one would go as far as to speak of "natural food", and this is quite impossible since our food is cooked. Even "raw vegetables" are subject to culinary preparation, with trimming, washing, cutting, addition of a sauce, etc. (Bocuse, 1976). (Bocuse, 1976). So no: there is nothing natural in our food, and the regulations should absolutely refuse the demagogic temptation to accept this term of naturalness about food products, because there is the source of conflicts about it.

8. Let's end this anthology with nitrates and nitrites, of which it will be observed that very few of those who speak of them have ever seen them (this is true for most of the compounds or products mentioned in this text). However, it is not difficult to go and scrape some walls to recover saltpetre (Guyon, 2006): it is a nitrate, which was once added to saltings (Anonymous, 1826) and which prevented botulism (Pascal, 2020)!
While nitrates and nitrites are denounced by some (National Assembly, 2020; Ligue contre le cancer, 2019), the food industry, which is threatened in its practices, has learned to cook hams in vegetable broths, where naturally present nitrates (truly naturally, this time) are transformed into nitrites by fermentation (Ifip, 2020). Thus, hams (for example) obtained in this way contain nitrates and nitrites like pieces to which nitrite salt, commonly used by pork butchers, has been added.
In other words, the ban on nitrates and nitrites in charcuterie leads to propose the banning of ham cooked with vegetables, which would be quite an achievement, especially since the micro-organisms that transform nitrates into nitrites are naturally present in the environment!


Excessive rigor?

Let's stop here, because we could fill volumes, and concentrate on the question initially asked: is it excessive, unnecessary rigor to be concerned with exact terminology when we talk about chemical species in public debates or in teaching? Is it a waste of time to ask for a precise terminology? Is it really necessary to avoid abuses of language and imprecision? And is it right to annoy your interlocutors by repeating in a nagging, even intrusive way that proteins are not "made of amino acids", but of "amino acid residues", for example? Should we accept to appear fastidious by recommending to our interlocutors to speak about D-glucose rather than glucose (we will not forget thalidomide)? Should we accept talking about "iron", when we know that the bioavailability of ionic iron (and not just any iron ion) is very different from that of heme iron in the blood (in the heme group of certain proteins), to the point that doctors who prescribe "iron" to combat deficiencies have to add the prescription of ascorbic acid, to increase this absorption (Cismef, 2020).
Let us first answer the question posed with an authoritative argument, by quoting Antoine-Laurent de Lavoisier: "It is while I was occupied with this work that I felt more clearly than I had done until then, the evidence of the principles that were laid down by the Abbé de Condillac in his logic, and in some of his other works. He establishes that we can only think with the help of words; that languages are true analytical methods; that the simplest, most exact algebra, best adapted to its object of all the ways of expressing itself, is at the same time a language and an analytical method; finally that the art of reasoning is reduced to a well-made language.  [...] The impossibility of isolating nomenclature from science, and science from nomenclature, is due to the fact that all physical science is necessarily founded on three things: the series of facts that constitute science, the ideas that recall them, and the words that express them [...] As it is words that preserve ideas, and transmit them, it follows that one cannot perfect languages without perfecting science, nor science without language" (Lavoisier, 1789).
As we can see, the idea of the brilliant creator of modern chemistry was clear... and who among us would dare to contradict him, on a point of thought? Who among us has done so much for science that he could feel superior to Lavoisier? Come on, a little modesty.
Then let's ask our interlocutors the question: why should we be embarrassed to use the right terms? After all, a botanist does not confuse a carrot with a turnip, and a forester does not confuse a fir with a spruce, and those who are neither botanist nor forester conform to the uses defined by these professionals, since it is up to them to initially make the difference. No disadvantage, finally, except to have to work to eradicate our own inaccuracies... but many advantages to precision in chemistry: whether it is a question of substance or form, the objective is to avoid empty speeches, to invite to go and see more closely, and to avoid that ideologists seize confusions to arrive at their masked and, sometimes, nauseating ends.
Yes, the rigor of terminology for chemical terms, as well as the coherence of units of measurement (Lavoisier also participated in their harmonization and in the creation of the Metric System), are the foundation on which sound collective decisions can be taken. It is therefore a condition of democracy.
In addition, the examination of words avoids unnecessary fears. For example, a few years ago, a consumer magazine headlined that some products contained "traces of potentially carcinogenic pesticide residues". The word "potentially" should already put us on the track of healthy doubt, because potentially carcinogenic does not mean carcinogenic. And exposure to the product is essential, because without exposure to a hazard, there is no risk (Pascal, 2020). The word "pesticide"? There are synthesized pesticides, on the one hand, but there are also compounds with which plants naturally protect themselves (Ames et al., 1990). We will not discuss here the relative merits and dangers of the two categories, especially since it would be better to consider the various "pesticides", natural or artificial, one by one, but let us insist: an apple, a carrot, a potato, protect themselves against aggressors by natural compounds... which are sometimes synthesized to use them as pesticides.
Residues of these pesticides? Let us suppose that a pesticide is carcinogenic, and that it is degraded: nothing proves that its "residues" (we would more correctly speak of degradation products) are also carcinogenic, and, even better, why couldn't residues of synthetic pesticides be beneficial? Basically, we are back to the question of triglycerides... but the word "residue" is used in a different sense... very vague!
Finally, the consumer magazine did not mention pesticides or pesticide residues... but traces of pesticide residues! Knowing that our chemical analysis equipment detects compounds at amounts as low as 10-15 mol/L (Kawai et al., 2020), we should first ask the question "how much? ", and to relate the amounts to toxicological values (tolerable daily intake, for example).
Finally, let us make a useful observation: often the mistakes that students of food science and technology make are the result of a misuse of terms, an imprecise use of words that they use without sufficient understanding. The corollary of this is that wishes for good terminology use must be accompanied by efforts at instruction: chemistry must be introduced as early as elementary school. After all, is it so difficult to think that water, for example, is made of many small moving objects (water molecules)? And then, to speak about what one does not know, to use words of which one is unaware of the meaning, to show one's ignorance by silly sentences... Still, we have our dignity, don't we?



References 

60 Millions de consommateurs. 2016. Des aliments en trompe-l’œil, https://www.60millions-mag.com /2016/06/08/des-aliments-en-trompe-l-oeil-10478, dernier accès 2021-01-15.

Académie d'agriculture de France. 2011. Que sont les produits alimentaires sains, loyaux et marchands, Séance publique du 27 avril 2011, https://www.academie-agriculture.fr/actualites/academie/seance/academie/que-sont-les-produits-alimentaires-sains-loyaux-et-marchands, dernier accès 2020-12-15.

Ames BN, Profet M, Schisky Gold L. 1990. Dietary pesticides (99.99% all natural), Proceeding of the National Academy of Sciences of USA,  87, 7777-7781.

Anonyme. 1826. La charcuterie ou L'art de saler, fumer, apprêter et cuire toutes les parties différentes du cochon et du sanglier. Editions Audor, Paris.

Anses. 2016. Le point sur les additifs alimentaires, https://www.anses.fr/fr/content/le-point-sur-les-additifs-alimentaires, dernier accès 2020-12-15.

Anses. 2020a. Les microplastiques, un risque pour l’environnement et la santé, https://www.anses.fr/fr/content/les-microplastiques-un-risque-pour-l%E2% 80%99environnement-et-la-sant%C3%A9, dernier accès 2020-12-15.

Anses. 2020b. Nanomatériaux dans l’alimentation : les recommandations de l’Anses pour améliorer leur identification et mieux évaluer les risques sanitaires pour les consommateurs, 9 juin 2020, https://www.anses.fr/fr/content/nanomat%C3%A9ri aux-dans-l%E2%80%99alimentation-les-recom mandations-de-l%E2%80%99anses-pour-a%C3% A9liorer-leur, dernier accès 2020-12-15.

Ansm. 2017. Levothyrox et médicaments à base de lévothyroxine, https://www.ansm.sante.fr/ Dossiers/Levothyrox-et-medicaments-a-base-de-levothyroxi ne/A-quoi-servent-les-medicaments-contenant-de-la-levothyroxine/(offset)/0, dernier accès 2020-12-15.

Assemblée nationale. 2020. Les sels nitrités dans l'industrie agro-alimentaire, http://www2.assemblee-nationale.fr/15/commissions-permanentes/commission-des-affaires-economiques/missions-d-information/les-sels-nitrites-dans-l-industrie-agro alimentaire, dernier accès 2020-12-15.

Bocuse P. 1976. La cuisine du marché, Flammarion, Paris.

Bru M. 2020. Organismes génétiquement modifiés : dans la tourmente des contradictions de la sécurité alimentaire, https://www.revueconflits.com/organismes-geneti quement-modifies-dans-la-tourmente-des-contra dictions-de-la-securite-alimentaire/, dernier accès 2020-12-15.

Cabioch J. 2020. TIMSS : Que retenir pour l'enseignement des sciences au collège ?, Le café pédagogique, http://www.cafepedagogique.net /lexpresso/Pages/2020/12/08122020Article637430181218329432.aspx, dernier accès 2020-01-8.

Cérou M. 2020. Acrylamide : de nouveaux aliments sous surveillance, Process alimentaire, https://www.processalimentaire.com/qualite/acrylamide-de-nouveaux-aliments-sous-surveillance, dernier accès 2020-12-15.

Chevreul ME. 1823. Recherches chimiques sur les corps gras d'origine animale, Berger Levrault, Paris.

Cismef. 2020. Acide ascorbique, http://www.chu-rouen.fr/page/acide-ascorbique, dernier accès 2020-12-15.

Condorcet N. 1791. Cinq mémoires sur l’instruction publique. http://classiques.uqac.ca /classiques /condorcet/cinq_memoires_instruction/cinq_memoires.html, dernier accès 2021-01-13.
Dgccrf. 1976. Les arômes alimentaires, https://www.economie.gouv.fr/dgccrf/les-aromes-alimentaires, dernier accès 2020-12-15.

Foodwatch. 2020. Pesticides, https://www. Food watch.org/fr/sinformer/nos-campagnes/alimentation-et-sante/pesticides/, dernier accès 2020-12-15.

Efsa. 2015. Scientific opinion on the re-evaluation of chlorophylls (E 140(i)) as food additives, https://www.efsa.europa.eu/fr/efsajournal/pub/4089, dernier accès 2020-12-15.

Florkin M, Stotz EH. 1972. A history of biochemistry. In Comprehensive biochemistry, 30, 292.

Gobley T. 1874. Sur la lécithine et la cérébrine, Journal de Pharmacie et de Chimie, 20,‎ 98-103, 161-166.

Greenfield H, Southgate DAT. 2007. Données sur la composition des aliments, Organisation des Nations Unies, FAO. http://www.fao.org/3/a-y4705f.pdf, dernier accès 2020-01-12.

Guyon E. 2006. L'Ecole normale de l'an III : Leçons de physique, de chimie, d'histoire naturelle. Presses de l'Ecole normale supérieure, Paris.

Ifip. 2020. Impact de sel nitrité ou de bouillon de nitrate fermenté, Gestion des qualités technologiques et sanitaire des produits, fiche 41, https://ifip.asso.fr/sites/default/files/pdf-documenta tions/fiche_2017_041.pdf, dernier accès 2020-12-15.

Inbp. 1990. Mon métier, boulanger, Editions J. Lanore, Paris.

INSERM. 2020, La consommation d’aliments moins bien classés au moyen du Nutri-Score associée à une mortalité accrue, https://presse.inserm.fr/la-consommation-daliments-moins-bien-classes-au-moyen-du-nutris core-associee-a-une-mortalite-accrue/40805/, dernier accès 2020-12-15.

IUPAC. 1978. The nomenclature of lipids (Recommendations 1976) IUPAC-IUB, Commission on Biochemical Nomenclature, Biochemical Journal, 171(1), 21-35.

IUPAC. 2004. Formulae, https://old.iupac. org/reports/provisional/abstract04/RB-prs310804/Chap4-3.04.pdf, dernier accès 2020-12-15.

IUPAC. 2019. Glycerides, Compendium of chemical terminology, 2nd ed. (The Gold Book), https://goldbook.iupac.org/terms/view/G02647, der-nier accès 2020-12-15.

Jacques J. 1981. Confessions d'un chimiste ordinaire, Le Seuil, Paris.

Jacques J. 1987. Berthelot : autopsie d'un mythe, Belin, Paris.

Kawai Y, Miyake Y, Hondo T, Lehmann JL, Terada K, Toyoda M. 2020. New Method for Improving LC/Time-of-Flight Mass Spectrometry Detection Limits Using Simultaneous Ion Counting and Waveform Averaging, Analytical Chemistry, 92, 9, 6579–6586.

Kressmann G. 2018. Risques réels et craintes infondées. Paysans & société, 368(2), 44-48.

Lacamp I. 2020. Les compléments alimentaires contenant du curcuma ou de la vinpocétine pourraient être dangereux, Sciences et avenir, https://www.sciencesetavenir.fr/sante/les-comple ments-alimentaires-contenant-du-curcuma-ou-de-la-vinpocetine-pourraient-etre-dangereux _141717 dernier accès 2020-12-15.

Lavoisier AL. 1789. Traité élémentaire de chimie, Cuchet, Paris.

Lide DR. 2005. CRC Handbook of Chemistry and Physics, Internet Version 2005, CRC Press, Boca Raton, Florida, http://www.hbcpnetbase.com, dernier accès 2020-12-15.

Ligue contre le cancer. 2019. Stop aux nitrites ajoutés, https://www.ligue-cancer.net/article/ 54352_ stop-aux-nitrites-ajoutes, dernier accès 2020-12-15.

Lower S. 2020. All about water, Chemistry Libretexts, https://chem.libretexts.org/ Book shelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Physical_Properties_ of_Matter/All_About_Water, dernier accès 2020-12-15.

Mary H. 2020. Traçabilité, additifs... 60 Millions de consommateurs s'attaque aux produits alimentaires ultra-transformés, https://www.usine nouvelle.com /article/tracabilite-additifs-60-millions-de-consomma teurs-s-attaque-aux-produits-alimentaires-ultra-transformes. N976911, dernier accès 2020-12-15.

Mills JS. 1874. La nature, Editions La Découverte (réédition 2003), Paris.

Myers RJ. 2012. What are elements and compounds, Journal of chemical education, 89(7), 822-833.

Naji JE. 2006. Citoyens et media: guide pratique pour un dialogue entre citoyens et media, www.UNESCO.org, CI/COM/VG/2006/RP/3, dernier accès 2020-12-15.

Ollivier D, Pinatel C, Ollivier V, Artaud J. 2014, Composition en acides gras et en triglycérides d’huiles d’olive vierges de 34 variétés et 8 Appellations d’Origine françaises et de 2 variétés étrangères implantées en France : constitution d’une banque de données, Olivae, 119, 36-48.

OPECEST. 2020. Office parlementaire d'évaluation des choix scientifiques et technologiques, http://www.senat.fr/opecst/, dernier accès 2020-12-15.

Pascal G, 2020. Rapport du groupe de travail « Impacts sur les cancers colorectaux de l’apport d’additifs nitrés (nitrates, nitrites, sel nitrité) dans les charcuteries », Académie d'agriculture de France, https://www.academie-agriculture.fr/ publi cations/publications-academie/avis/rapport-impacts-sur-les-cancers-colorectaux-de-lapport, dernier accès 2020-12-15.

Passeport santé. 2020. Les sels minéraux : tous sur ces micro nutriments indispensables, esNutriments/Fiche.aspx?doc=sels-mineraux_nu, dernier accès 2020-12-15.

PNNS. 2020. Manger bouger : les huiles riches en acides gras polyinsaturés, https://www. mangerbouger.fr/pro/sante/alimentation-19/nouvelles-recommandations-adultes/rubri que-test/e-les-huiles-riches-en-acides-gras-poly insatures.html, dernier accès 2020-12-15.

Pons A, Allamy L, Schüttler A, Rauhut D, Thibon C, Darriet P. 2017. What is the expected impact of climate change on wine aroma compounds and their precursors in grape?, OENOOne, Institut des Sciences de la Vigne et du Vin, 51 (2-3), 141-146.

Pouliquen F. 2020. Charcuterie : La ligue contre le cancer, Yuka et Foodwatch demandent l’interdiction des nitrites, 20 Minutes, 4 février 2020, https://www.20minutes.fr/sante/2710507-20200204-charcuterie-ligue-contre-cancer-yuka-foodwatch-demandent-interdiction-nitrites, dernier accès 2020-12-15.

Santé Magazine. 2020. L’alimentation est bien un facteur de risque pour le cancer de la prostate, Santé Magazine, 29 juillet 2020, https://www.santemagazine.fr/actualites/actualites-alimentation/lalimentation-est-bien-un-facteur-de-risque-pour-le-cancer-de-la-prostate-650766, dernier accès 2020-12-15.

Sniaa. 2020. Définition. http://www.sniaa. Org/ arome#definition, dernier accès 2020-12-15.

This P, Panel P. 2010. La décision médicale partagée en gynécologie, Gynécologie Obstétrique & Fertilité, 38, 126-134.

Thom R. 1970. Les mathématiques « modernes », une erreur pédagogique et philosophique ?, L’Age de la science. http://gaogoa.free.fr/HTML /Textes/Les%20Mathematiques%20Modernes%20 par%20R.THOM.pdf, dernier accès 2021-01-13.

TLFi. 2020a. Arôme, http://stella.atilf.fr/ Dendien/scripts/tlfiv5/advanced.exe?8;s=1754745 780, dernier accès 2020-12-15.

TLFi. 2020b. naturel, http://stella.atilf.fr/Dendien /scripts/tlfiv5/visusel.exe?14;s=1387088820; r=1;nat=;sol=9, dernier accès 2020-12-15.

This H. 2019. Parlons des chlorophylles, et pas de la chlorophylle !, Encyclopédie, « Questions sur », Académie d’agriculture de France, https://www.academie-agriculture.fr/sites/default/files/publications/encyclopedie/final_s8-07_parlons _des_chlorophyles.pdf, dernier accès 2020-12-15.

Van Aubel M. 1963. Accident, catégories et prédicables dans l'œuvre d'Aristote, Revue Philosophique de Louvain.Troisième série, 61(71), 361-401.

Vaulpré J, Jaffé J. 2020. Réformer dans un climat irrationnel, le nouveau défi des politiques, https://www.lesechos.fr/idees-debats/cercle/reformer-dans-un-climat-irrationnel-le-nouveau-defi-des-politiques-1161763, dernier accès 2020-12-15.

Edité par
Nicole Moreau, Membre de la Société chimique de France et ancien Président de l'IUPAC. Président du Comité scientifique du Programme International pour les Sciences fondamentales (PISF) de l'UNESCO.

Rapporteurs
Nicole Moreau, Membre de la Société chimique de France et ancien Président de l'IUPAC. Président du Comité scientifique du Programme International pour les Sciences fondamentales (PISF) de l'UNESCO.

Jean-Pierre Foulon, ancien professeur de chimie en Spéciales au Lycée Henri IV à Paris. Membre du Comité de rédaction de l'Actualité Chimique (SCF).


Rubrique
Cet article a été publié dans la rubrique « Opinions » des Notes Académiques de l'Académie d'agriculture de France.

Reçu
17 novembre 2019

Accepté
3 janvier 2021

Publié
13 janvier 2021


Citation
This H. 2021. La rigueur terminologique pour les concepts de la chimie : une base pour des choix de société rationnels, Notes Académiques de l'Académie d'agriculture de France / Academic Notes from the French Academy of Agriculture, 2021, 1, 1-15.



Hervé This est physico-chimiste dans l'UMR 0782 SayFood INRAE - AgroParisTech, professeur consultant à AgroParisTech, membre de l'Académie d'agriculture de France, membre correspondant de l'Académie royale des sciences, arts et lettres de Belgique et de l'Académie de Stanislas, membre de l'Académie d'Alsace, sciences, lettres et arts.

Let's avoid using the word "polyphenoll"

Indeed there is no reason to speak of polyphenols, as the International Union of Chemistry decided : 

Phenols : Compounds having one or more hydroxy groups attached to a benzene or other arene ring, e.g. 2-naphthol:
Source : PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity  intermediates based on structure (IUPAC Recommendations 1995)) on page 1357
https://doi.org/10.1351/goldbook.P04539

From now on, I shall speak of phenols. 

PS. By the way, tannins are very specific phenols.

Obituary: Christian Ducauze

 Christian Ducauze (June 15, 1943, Sainte-Livrade-sur-Lot - August 22, 2021, Paris), a life of teaching analytical chemistry



Hervé This,
International Center for Molecular Gastronomy INRAE-AgroParisTech.




The card that friends of Christian Ducauze sent to his widow on the occasion of his death showed an Asian master handing a book to a student. A representation of North Africa would also have been appropriate, as Christian Ducauze began his career with several years in Tunis, but it did emphasize one of the main aspects of his career, dedicated to transmission. Unfortunately we did not find a card that would expression that, for Christian Ducauze as for us, chemistry is a central science, essential - he repeated - for the initiation of agronomy students to the handling of complex systems, such as those found in food and the environment.


From Strasbourg to Tunis, then to Paris

Christian Ducauze was proud to owe his training as a chemist to the École Nationale Supérieure de Chimie in Strasbourg, starting in 1963. Graduating as a chemical engineer in 1966, he continued his training with a Master's degree in electrochemistry, then with a PhD at the CEA, still in Strasbourg, during which he developed an electroanalysis method -differential oscillographic voltammetry- for the determination of trace elements in solution (cadmium and copper in particular).
In 1970, he left France to do his military service as an Assistant Professor at the National Agronomic Institute of Tunisia, which, created in 1898, is the oldest school of agronomy in Africa. He stayed there for six years, learning the profession of professor and laboratory director, as well as the implementation of statistical methods for the determination of traces of magnesium. It was in Tunis that he met Larbi Bouguerra, a specialist in environmental chemistry, who became one of his friends.
In 1976, he passed the competitive examination to become a professor of analytical chemistry at what was then the Institut National Agronomique Paris-Grignon (INA-PG): among the friends who helped him for the preparation of his selection lesson were Jean-Yves Le Déaut, assistant professor of biochemistry at the University Louis Pasteur in Strasbourg, whom he had known in Tunis, where he was also teaching, and who would shortly afterwards become president of the Parliamentary Office for the Evaluation of Scientific and Technological Choices, but also Charles Kappenstein (today professor emeritus at Poitiers, who had shared Christian Ducauze's office at the end of the 1960's on the 10th floor of the "Chemistry Tower", in Strasbourg).
Christian Ducauze knew very well that he was arriving in a « grande école » (i.e., a university with a strong selection) that, from its inception, had been teaching analytical chemistry at the highest level: the first « Institut National Agronomique », created in Versailles in 1848, included a chair of general chemistry and analysis, whose incumbent was Charles Adolphe Würtz, member of the French academy of sciences, Dean of the faculty of medicine, and professor at the Sorbonne. After the second Institut National Agronomique was transferred in 1890 to 16 rue Claude Bernard, the chemistry professorships went to Émile Péligot, Jean-Baptiste Boussingault, Achille Müntz,  Antoine-Charles Girard, Maurice Lemoigne, most of them members of the French Academy of sciences or of the French Academy of agriculture.
So many great names! However, when Christian Ducauze arrived at what had become INA P-G, there were above all the premises and the wish of the Institute's administration to see chemistry well taught, but no research laboratory, no competent personnel, and no equipment: Christian Ducauze inherited only a pH-meter and a UV-visible spectrometer, moreover without a recorder. Everything had to be done, while the financial means could only be obtained if a certain level of credibility was first achieved.
However, Christian Ducauze was active and found support from the Ministry of the Environment, the CNRS, the Compagnie Générale des Eaux and, finally, the Ministry of Research, while he created original teaching programs to adapt a course of analytical chemistry to the very specific training needs of agricultural students, different from those of students in chemistry schools or university analytical chemistry departments.
In 1978, having understood the importance of continuing education, he organized advanced training sessions entitled "Current techniques in the service of chemical analysis": these three-day courses were oriented, the first towards elementary analysis and the second towards structural organic analysis. At the time, this continuing education activity was both a source of income for the laboratory and a showcase for the strengths of the teaching and research, but it was also an opportunity to measure, with engineers from the public and private sectors, the adequacy of the teaching to the problems that agricultural engineers would soon encounter. It was also an opportunity to see the considerable national needs for training in analytical chemistry, as the universities had not fully met these needs.
The European School of Analytical Chemistry (EECA) was therefore created with, at its head, an international scientific committee of about forty members, chaired by Christian Ducauze, to define the major training programs. Five disciplinary fields were considered: separative methods (all chromatography and capillary electrophoresis); spectrometric methods (essentially atomic absorption spectroscopy and nuclear magnetic resonance); quality, data processing and management (chemometrics, quality assurance, etc.); sensory analysis (all aspects); specific applications (characterization of materials, environment, food, pharmaceutical products, etc.). The success of the EECA is then attested by numerous requests from industry, in particular the food industry, and also by the European Economic Community, which entrusts training courses to help the scientific and technological development of Eastern European countries.
Then, from 1982, the co-habilitation for a new master program, followed by the educational reform set up at the INA P-G, obliged to rethink the whole training in analytical chemistry at the School, so that this time a training of engineers by apprenticeship and a tutoring of students of this new training were set up.

The birth of French chemometrics

Statistical methods were used in many of the laboratory's research projects, and a new discipline was soon created, called "chemometrics", which is now defined as the use of statistical methods to process chemical analysis data. It allows to re-analyze the notion of analytical chemistry, which will be, much later, the subject of a reference book published by Lavoisier Tec et Doc (C. Ducauze, Chimie analytique, analyse chimique et chimiométrie). The development of these methods has been fundamental for both research and teaching (Rutledge and Ducauze, 1991; Ducauze and Bermond, 1992; Eveleigh, 1994; etc.).
The idea of chemometrics has led to renovations in laboratory practices and quality assurance, providing effective tools to deal with a wide variety of applications: studies of animal products (Gerbanowski et al., 1997) or plants (Maalouly et al., 2004), analytical methodology and valorization of chemical analysis data (Feinberg et al., 1991; Guesnier et al., 1993; Hernandez et al. 1994), etc. These contributions led the European Economic Community to provide financial support to the Analytical Chemistry Laboratory in the framework of a European project for the teaching of chemometrics: Applied information technology for the chemical, pharmaceutical and agrofood industry (COMETT project - leader: D.L. Massart, VUB, Belgium).
For research at the Analytical Chemistry Laboratory of INA P-G, new application topics were chosen, with, obviously, overlaps between fields.
First of all, the analytical studies of metals (lead, cadmium, mercury, in particular) concerned various matrices, such as soils or waters, for example (in particular with Alain Bermond, then Valérie Camel and Nastaran Manoucheri), notably with the support of the Ministry of the Environment: speciation of mercury (Ireland-Ripert et al,  1982; Ireland-Ripert, 1982; Besson, 1981), modelling of pollution (Godin et al., 1985), migration towards the water table and passage in plants (Feinberg et al., 1987; Heuillet et al., 1988; Heuillet et al., 1988)...
In this field of the environment, the media imposed the implementation of analytical techniques different from atomic absorption or electrochemistry: HPLC (El Din et al., 1984), GC-MS, infrared spectroscopy (Maalouly et al., 2004), fluorescence spectroscopy ... always in the various media (Jarret et al., 1985; Jan et al., 1988; Jarret et al., 1983):
At the same time, environmental concerns led to studies of agri-food matrices, first for metals, but then for many other compounds. Initially, the complexity of the matrices to be analyzed led to an interest in the problem of sample preparation and, initially, the laboratory developed a rapid and efficient high-temperature calcination method for the determination of lead, cadmium and copper in foods (Feinberg and Ducauze, 1980). For the same reason, it was necessary at the same time to learn how to control the interferences occurring at the time of measurement (Feinberg and Ducauze, Analusis, 1980). Overcoming these difficulties again required the use of statistical methods. And we should not forget the studies of wines, with works often presented at the congresses In Vino Analytica Sciencia (Cheynier et al., 1983; Rutledge et al., 1993; Belaiche et al., 1996; Delgadillo et al., 2001; Delgadillo, 2004), as well as the studies of glycation reactions (Birlouez-Aragon et al., 2004)


The international influence

When the laboratory was attached to the Food Industry Sector of INRA (Department of Consumer Sciences), in 1984, Christian Ducauze wanted to find a better balance of research activities between the environmental and food industry fields. As early as 1986, a team from the laboratory sought to reduce the time needed to prepare samples by implementing low resolution impulse nuclear magnetic resonance (IR-NMR). This method was already used in the fat industry, but its considerable potential had been little explored. The NMR-IBR allowed, at first, to develop fast control methods, useful in margarine industry (Rutledge et al., 1988; El Khaloui et al., 1990). This initial work led the laboratory, and in particular Douglas Rutledge, to be invited to join the Coordinating Committee of Concerted Action No. 1 of the FLAIR program. Having acquired a good command of the apparatus, the team then embarked on more difficult studies on the states and dynamics of water in food (Monteiro-Marques et al., 1991; Monteiro Marques et al., 2007),
Christian Ducauze was well aware that NMR was an essential tool for chemical analysis: was he not close to Gérard and Maryonne Martin, who had invented the SNIF-RMN natural isotope fractionation method, at the University of Nantes, to verify the origin and purity of many foods and beverages, in cases where traditional analytical methods fail to detect counterfeits? These relationships continued with Eurofins, the company created in 1987 by Gilles Martin, the inventors' son.
And, above all, all this research, with the use of NMR or other analytical techniques, was widely disseminated: by the EECA, as we have seen, but also by the international journal of analytical chemistry Analusis , of which Christian Ducauze was editor-in-chief for several years, and by the participation in various European working groups (Working Party on Food Chemistry and Division of Analytical Chemistry of the Federation of the European Chemical Societies, now EuChemS), where he created relationships with foreign universities and colleagues. Through these relationships with colleagues from all over the world, students came in great numbers: from 25 countries! Moreover, the Analytical Chemistry Laboratory organized international scientific conferences such as EuroAnalysis, EuroFoodChem, GAMS, In Vino Analytica Scientia...
But to enumerate, one risks to forget some actions, so much they were numerous! How can we not mention the theses that Christian Ducauze personally directed, in relation with Lebanon, Vietnam? How can we forget the joint teaching activities with the University of Nantes, where analytical chemistry was already present, but where the INA-PG team was important for the chemometric contributions? How can we forget the master "Research and development in analytical strategy", which was born from the collaboration with Arlette Baillet, at the Faculty of Pharmacy of Chatenay-Malabry?

Strategic analyses

As we have seen, Christian Ducauze has constantly sought to adapt the development of the laboratory to training needs, taking into account the pedagogical reform carried out at the INA P-G. The latter led him to examine in greater depth the specificity of the agricultural engineer and to conclude that his essential characteristic was his ability to apprehend problems at different scales: molecular, organized being, macro-system (economy, environment).
For the first two, the teaching that had been created responded well to this training objective, whether it was the atomic and molecular approach or the study of agri-food matrices and complex environments. On the other hand, macro-systems were less studied. In addition to the first and third year options introduced by Alain Bermond in the field of the environment, a need was felt, through quality control, on production in the field of the agro-food industries. In 1990, Christian Ducauze predicted that, in the future, the industrial control laboratory would no longer be considered as a means of repression, but would become the real pilot of the production units. In retrospect, we can see that the question of "control" in companies is complex, but that, in any case, the questions of regulations, in relation to analysis, have become essential, so much so that the industry has understood that sanitary errors must be absolutely avoided.
Christian Ducauze had other "political" convictions: he was convinced that the acceptance of an innovation by society is the condition for its diffusion. Innovation in agriculture illustrates the increasing divorce between the perception of citizens and the word of scientists. He was convinced that it was necessary to better organize the debate between the scientific world, the political world and the citizens: it seemed to him to be essential "to imagine new means, methods and places of debate to train and inform the public in a transparent way".
He analyzed that one of the worrying evolutions of our society was based on the increasingly marked confusion between what comes from a rigorous scientific approach and what comes from beliefs or manipulations. He was convinced that in the field of agriculture, innovation can give society a vision for the future and shed light on the issues of tomorrow. He participated in the establishment of this dialogue by transmitting his knowledge. And this is how he had ongoing discussions, notably with Jean-Yves Le Déaut, or with the journalist Olivier Lesgourgues, known in particular to science lovers on M6.
To conclude, I can testify, on the basis of numerous discussions with Christian Ducauze, that his actions in what became AgroParisTech from the National Agronomic Institute, did not forget that the School was born with an essential place for chemistry, born of the needs of agronomy at the time of the founders: for Würtz or Boussaingault, as for Justus von Liebig and many of his students, the question of synthetic fertilizers was of prime importance. Today, at a time when questions of sustainability, the environment, food safety (particularly with molecular biology methods), food safety and nutrition are being raised, knowledge of chemistry, its contribution and its dissemination have never been so essential.

This tribute to Christian Ducauze benefited from the testimonies of Douglas Rutledge and Luc Eveleigh, Jean-Yves Le Déaut, Charles Kappenstein.

La science des aliments n'est pas la technologie des aliments

Il y a toujours eu une confusion entre science et technologie, au point que Louis Pasteur le déplorait déjà, avec des phrases d'une énergie terrible.



Pourtant, c'est tout simple, en principe :
D'une part, les sciences de la nature cherchent  à "lever un coin du grand voile", à découvrir les phénomènes inconnus et les mécanismes des phénomènes, à l'aide une méthode aussi certaine que possible, et qui passe par :
(1) l'identification d'un phénomène ;
(2) la caractérisation quantitative de ce phénomène (on en mesure des caractéristiques judicieusement choisies)
(3) le regroupement des résultats de mesure en "lois" synthétiques, c'est-à-dire essentiellement en équations ;
(4) la recherche -par induction, c'est là un point central- de concepts, notions, théories, mécanismes quantitativement compatibles avec les équations dégagées ;
(5) la recherche de conséquences des théories ainsi "induites" ;
(6) les tests expérimentaux de ces conséquences, en vue de réfutations qui permettent de boucler, afin d'améliorer des théories toujours insuffisantes.



D'autre part, la ou les technologies (à discuter), elles, visent l'amélioration des techniques, et elles ont un but pratique, puisque "technique" signifie "faire".



Pour autant, la science n'est pas au-dessus de la technologie, et la technologie n'est pas au-dessus de la science : ce sont deux activités séparées ! Et Pasteur lui-même observait que sa volonté de contribuer au bien-être de l'humanité l'avait détourné de ses travaux scientifiques (par exemple, l'exploration de la chiralité) vers la technologie, mais il l'avait mûrement décidé.



Des collègues évoquent, à côté de ces termes de science et de technologie, celui d'ingéniérie, mais il n'est pas bien clair, et, en tout cas, il tombe clairement du côté de la technologie, puisque le Journal officiel en dit :
"Ensemble des fonctions allant de la conception et des études à la responsabilité de la construction et au contrôle des équipements d'une installation technique ou industrielle (en anglais : engineering)"
 (Arrêté du 12 janv. 1973 ds Lang. fr., Paris, J.O., 1980, p. 21).
Bien sûr, certains peuvent utiliser les termes avec diverses acceptions idiosyncratiques... mais ils risquent de n'être compris que par eux-mêmes.



Ajoutons enfin  :
 - que le mot « science », utilisé dans une expression telle que « science du coordonnier » n'a rien à voir avec les sciences de la nature, puisque, ici, le mot « science » signifie seulement savoir ; or comment refuser à un corps professionnel d'avoir un savoir ? Ce serait idiot… tout comme il serait idiot de confondre ce savoir empirique avec les sciences de la nature
- que  les mathématiques ne sont pas des sciences de la nature, mais des "mathématiques", et elles ne se confondent pas avec le calcul, qui est, comme on l'a vu, le quotidien des sciences de la nature
- qu'il ne peut en aucun cas exister des "sciences appliquées", puisque des science ne sont précisément pas appliquées ; une expression comme "sciences appliquées" est un oxymore fautif, tout comme carré rond.






Tout cela étant dit, puisque la confusion règne (c'est un fait) beaucoup en "sciences et technologies des aliments", et que les étudiants notamment sont perdus, je me suis amusé à recopier la table des matières d'une revue de la discipline pour essayer d'y voir plus clair. A noter que le mot "chimie" figure dans son titre, et que ce mot, déjà, prête à confusion, comme je l'ai expliqué dans d'autres billets, puisque l'on a tendance à confondre dans ce mot... de la science, de la technologie, et même de la technique.
Pourtant, un examen attentif de l'histoire de la chimie montre que la chimie est une science de la nature, et que les travaux techniques (industries) ou technologiques ne sont pas de la chimie proprement dite, mais de la technologie ou de la technique, des applications de la chimie qui ne devraient pas être nommées "chimie".
On est proche de la confusion qui règne en médecine, si bien dénoncée par Claude Bernard, qui observe justement que la médecine est une technique, que la recherche clinique est une technologie, et que la science de la médecine est la physiologie !






Mais lançons nous... même si, on va le voir, l'exercice finit par être lancinant.
 
Bioactive compounds of beetroot and utilization in food processing industry: A critical review : ici, au moins, on commence facilement, car il est question d'utiliser des composés des betteraves dans l'industrie. C'est clairement de la technologie. Certes, il aura fallu identifier les composés "bioactifs" avant de les étudier, mais l'intention est claire. Intention ! Le mot est essentiel, parce que l'on peut fort bien imaginer que des ingénieurs ou des technologues, voire des techniciens, s'intéressant à leur travail, fassent une découverte, mais il faudra l'intention, pour aller plus loin, et c'est à ce titre que l'on a parfois dit que Rumford avait découvert la convection.
Je reviens une seconde sur mon "Certes, il aura fallu identifier les composés bioactifs" : on voit qu'un travail technologique peut conduire à explorer le monde, à "lever un [petit, ici] coin du grand voile", ce qui correspond à une activité scientifique.
Et  s'impose une observation : de même que l'on ne fait pas de chimie quand on respire, on ne fait pas de science quand on effectue certaines des tâches qui relève de sa méthode ; de même, une partie du public confond science et rigueur, mais il ne suffit pas d'être rigoureux pour faire une recherche scientifique. L'intention est essentielle, et les technologues qui auront ici identifié des composés bioactifs dans les betteraves, s'ils ont contribué à l'augmentation des connaissances, n'auront pas notablement contribué à la science. D'ailleurs, des composés "bioactifs" : on pressent qu'il s'agit seulement d'observer si des composés ont une action sur le corps humain... ce qui est une application.
J'ajoute aussi que je crois les étapes 4, 5 et 6  essentielles dans la recherche scientifique. Trop souvent, le travail n'est que technique, quand il s'arrête à la caractérisation quantitative des phénomènes.



Exploring the impacts of postharvest processing on the aroma formation of coffee beans – A review :  ce deuxième travail semble annoncer clairement la couleur : il s'agit d'explorer un champ technique, à savoir ce qui se passe quand on a recueilli les fruits du caféier. Toutefois le titre n'est plus suffisant, ici, parce que l'on pourrait imaginer que les « chercheurs » ont tenté d'élucider des mécanismes à des fins de savoir, ou bien à des fins d'amélioration des procédés. On retrouve ici la question de l'intention, de l'ambition particulière de ce « chercheur » qui, selon les cas, est un chercheur scientifique ou un chercheur technologique.
En tout cas, ici, il faut y aller plus avant pour se déterminer... en se doutant que si l'on parle d'arôme, c'est bien que l'on pense à un effet sur l'humain... et donc à de la technologie, en vue de modifier le café pour qu'il soit mieux apprécié : si ce n'est pas de la technologie, cela !



Phenolic compounds and antioxidant activities of tea-type infusions processed from sea buckthorn (Hippophaë rhamnoides) leaves : ici, le mot "proccessed" fait penser à de la technologie, mais nous arrivons à un cas plus subtil, même si l'argousier est utilisé de façon technique. Ce qui est en cause, plus précisément, c'est cette exploration des activités antioxydantes des composés phénoliques de la plante. Vise-t-elle une simple caractérisation, pour une utilisation (technologique), ou la recherche de mécanismes ? Il faut lire en détail l'article... et l'on opte alors pour la seconde option.
Mais là encore, une observation, à propos de ce "processed" : le fait que des composés phénoliques soient différents avant ou après transformation de feuilles d'argousier est un phénomène dont l'exploration pourrait révéler des mécanismes inédits du monde... à condition d'être dans l'état d'esprit de les chercher. C'est  sans doute dans cette idée que l'un de mes amis qui est un très bon scientifique évoque, parmi les stratégies scientifiques, le "abstraire et généraliser".



Chloroplast-rich material from the physical fractionation of pea vine (Pisum sativum) postharvest field residue (Haulm) : là, c'est facile, puisque c'est une valorisation de résidus de transformation. Technologie.
Bien sûr, avec beaucoup de mauvaise foi, on pourrait dire que l'on s'intéresse aux mécanismes particuliers qui permettent à des résidus du pois de contenir beaucoup de matériaux chloroplastiques, mais... la lecture de l'article montre que tel n'est pas le cas, puisque, au contraire, il s'agissait d'analyser technologiquement les nutriments des fractions isolées, par une technique un peu améliorée.



Characteristics of flavonol glycosides in bean (Phaseolus vulgaris L.) seed coats : ici, il s'agit donc de caractériser une classe particulière de composés dans les haricots, et l'on peut imaginer que l'objectif est de lever un coin du grand voile. D'ailleurs, la "science des aliments" n'est en réalité une science de la nature, et non une activité technologique, que dans la mesure où elle a cet objectif. On observera que nous avions eu le besoin d'introduire la gastronomie moléculaire comme une discipline scientifique, parce que avions vu que les "sciences et technologies des aliments", dans les années 1980, se résumaient presque à de la science des ingrédients, et à des études des procédés ; or il nous apparaissait clairement que nous pourrions identifier des phénomènes et mécanismes nouveaux si nous explorions des phénomènes peu considérés, avec l'objectif clair d'identifier des mécanismes et phénomènes nouveaux.
Bref, ici, il pourrait s'agir de science des aliments, et bien de science... sauf que la consultation de l'article révèle un "Results suggest seed coats of Windbreaker and Eclipse may have potential as functional food ingredients, though benefits may not be simply due to flavonols"... qui montre que le travail était technologique. 



Wine production using free and immobilized kefir culture on natural supports : hopla, facile, non ? Mais c'est aussi l'occasion de voir que, jusque ici, nous n'avons pas eu un seul cas de science !



Variations in chlorophyll and carotenoid contents and expression of genes involved in pigment metabolism response to oleocellosis in citrus fruits: ouf, voilà enfin de la science ! Ici, de la science qui caractérise non pas les aliments, mais bien plutôt les ingrédients alimentaires, car c'est là une subtilité que je gardais en réserve, et qui agravait l'état des années 1980  : non seulement la science des aliments n'était le plus souvent que de la science des ingrédients, mais pire, ce n'était pas de la science des aliments, puisque c'était de la science des ingrédients ! Or je maintiens que les ingrédients ne sont pas des aliments, puisque manque l'étape de "cuisine". Un exemple : un sanglier vivant n'est pas un aliment ; pour faire un aliment à partir de ce sanglier, il aura fallu tuer l'animal, le dépecer, le préparer, le "cuisiner"... Ce qui n'est pas une mince affaire, et ce qui change du tout au tout la chair de l'animal.



Use of a smartphone for visual detection of melamine in milk based on Au@Carbon quantum dots nanocomposites : et là, c'est facile, puisque c'est de la caractérisation technique. N'épiloguons pas



Physicochemical properties and phenolic content of honey from different floral origins and from rural versus urban landscapes : à la lecture du seul titre, les deux possibilités scientifique et technologique se présentent, à savoir que l'on pourrait explorer les compositions et des caractéristiques des miels de différentes origines, en vue de comprendre comment ils sont formés, par exemple, ou bien l'on pourrait chercher  à attribuer des propriétés à partir de l'environnement de production, mais je propose surtout de conserver cet exemple observer que certains travaux publiés s'arrêtent à la caractérisation : si l'on est charitable, on peut admettre qu'il s'agisse de science, avec une ou deux étapes préliminaires... mais la caractérisation n'a de sens que si l'on identifie des mécanismes !



Effect of interesterified blend-based fast-frozen special fat on the physical properties and microstructure of frozen dough  : bon, de la technologie. Là encore, on pourrait faire de la science si l'on était vraiment scientifique... mais
Effect of phosphates on gelling characteristics and water mobility of myofibrillar protein from grass carp (Ctenopharyngodon idellus) : on se trouve dans l'avant dernier cas, et l'on pose la question de l'objectif, avant de trancher. L'article, lui, nous dit qu'il s'agit de technologie : dommage pour la science, tant mieux pour la technologie.



Hydrolysis and oxidation of lipids in mussel Mytilus edulis during cold storage : je pressens un travail technologique. Car même si l'on caractérise l'évolution des lipides lors du stockage au froid, l'étude s'arrête là.

Particulate organohalogens in edible brown seaweeds : de la science des ingrédients ou de la toxicologie ? Cette fois, il faut aller voir l'article, dont le résumé est le suivant :



Brown algae, rich in antioxidants and other bioactive compounds, are important dietary seaweeds in many cultures. Like other marine macroalgae, brown seaweeds are known to accumulate the halogens iodine and bromine. Comparatively little is known about the chemistry of chlorine in seaweeds. We used synchrotron-based X-ray absorption spectroscopy to measure total non-volatile organochlorine and -bromine in five edible brown seaweeds: Laminaria digitata, Fucus vesiculosus, Pelvetia canaliculata, Saccharina latissima, and Undaria pinnatifida. Organochlorine concentrations range from 120 to 630 mg·kg-1 dry weight and organobromine from 150 to 360 mg·kg-1, comprising mainly aromatic organohalogens in both cases. Aliphatic organochlorine exceeds aliphatic organobromine but is positively correlated with it among the seaweeds. Higher organochlorine levels appear in samples with more lipid moieties, suggesting lipid chlorination as a possible formation pathway. Particulate organohalogens are not correlated with antioxidant activity or polyphenolic content in seaweed extracts. Such compounds likely contribute to organohalogen body burden in humans and other organisms.
On voit que le résumé commence par vendre la salade, en termes d'application technique. Cela dit, le métabolisme du chlore ou du brome est une question passionnante. On n'oublie pas que l'iode fut découvert à partir des algues par Bernard Courtois.



Comparative studies on the yield and characteristics of myofibrillar proteins from catfish heads and frames extracted by two methods for making surimi-like protein gel products : bon, l'intention technologique est claire.



Point-of-use detection of ascorbic acid using a spectrometric smartphone-based system : idem.



Development and validation of a method for simultaneous determination of trace levels of five macrocyclic lactones in cheese by HPLC-fluorescence after solid–liquid extraction with low temperature partitioning : de l'analyse, donc de la technologie.



Rapid quantification of the adulteration of fresh coconut water by dilution and sugars using Raman spectroscopy and chemometrics : de la caractérisation, en vue de dépister des fraudes, c'est donc de la technologie.



Effect of pH and holding time on the characteristics of protein isolates from Chenopodium seeds and study of their amino acid profile and scoring : en réalité, il faut lire l'article pour voir que l'on est dans une caractérisation technologique.



Antioxidant activity of a winterized, acetonic rye bran extract containing alkylresorcinols in oil-in-water emulsions : là encore, on trouve le cas évoqué. Mais là, je commence à me lasser, et sans doute vous aussi.



Chemical profiles and antioxidant properties of roasted rice hull extracts in bulk oil and oil-in-water emulsion : il s'agit donc de caractérisation, et c'est l'occasion de signaler à nos jeunes amis qu'une caractérisation n'est qu'une caractérisation. Le contenu conceptuel est faible si l'on ne va pas jusqu'aux mécanismes. Mais, au fait, trouver le mécanisme d'un phénomène, c'est bien... mais est-ce une grande découverte ?



Distribution and effects of natural selenium in soybean proteins and its protective role in soybean β-conglycinin (7S globulins) under AAPH-induced oxidative stress: on sent la technologie à plein nez... Mais je propose que nous arrêtions ici, parce que c'est vraiment trop long, en observant seulement que les travaux scientifiques sont vraiment rares ! N'est-ce pas désolant ? N'est-ce pas un scandale que la revue en question évoque les sciences aliments.



Mais je dis assez souvent que se lamenter est inutile, et je vois surtout, là, la possibilité de développer véritablement des sciences des aliments, et pas seulement des ingrédients alimentaires ! Cela, ce me semble être précisément la gastronomie moléculaire !!!!!!!!!!!!!!!!!!!!!!!!!!!




Annexe: le reste des titres, pour que vous puissiez vous exercer

# Peels of tucumã (Astrocaryum vulgare) and peach palm (Bactris gasipaes) are by-products classified as very high carotenoid sources
# Diffuse light affects the contents of vitamin C, phenolic compounds and free amino acids in lettuce plants
# Solid-state fermentation of black rice bran with Aspergillus awamori and Aspergillus oryzae: Effects on phenolic acid composition and antioxidant activity of bran extracts
# Modifying Robusta coffee aroma by green bean chemical pre-treatment
# Microwave and ultrasound pre-treatments to enhance anthocyanins extraction from different wine lees
# Effect of sex on the nutritional value of house cricket, Acheta domestica L.
# Effect of anthocyanins on lipid oxidation and microbial spoilage in value-added emulsions with bilberry seed oil, anthocyanins and cold set whey protein hydrogels
# Comparison of real-time PCR methods for quantification of European hake (Merluccius merluccius) in processed food samples
# A unified approach for high-throughput quantitative analysis of the residues of multi-class veterinary drugs and pesticides in bovine milk using LC-MS/MS and GC–MS/MS
# Novel insight into the role of withering process in characteristic flavor formation of teas using transcriptome analysis and metabolite profiling
# High-sensitivity determination of cadmium and lead in rice using laser-induced breakdown spectroscopy
# Characterization and storage stability of chlorophylls microencapsulated in different combination of gum Arabic and maltodextrin
# Determination of serotonin in nuts and nut containing products by liquid chromatography tandem mass spectrometry
# Development of a DNA metabarcoding method for the identification of fifteen mammalian and six poultry species in food
# Comparisons of nutritional constituents in soybeans during solid state fermentation times and screening for their glucosidase enzymes and antioxidant properties
# Characterization of three different types of extracellular vesicles and their impact on bacterial growth
# Taste-guided isolation of sweet-tasting compounds from grape seeds, structural elucidation and identification in wines
# A value-added approach to improve the nutritional quality of soybean meal byproduct: Enhancing its antioxidant activity through fermentation by Bacillus amyloliquefaciens SWJS22
# UV and storage stability of retinol contained in oil-in-water nanoemulsions
# Screening of antimicrobials in animal-derived foods with desorption corona beam ionization (DCBI) mass spectrometry
# Effect of hulling methods and roasting treatment on phenolic compounds and physicochemical properties of cultivars ‘Ohadi’ and ‘Uzun’ pistachios (Pistacia vera L.)
# Traditional rose liqueur – A pink delight rich in phenolics
# In vivo anti-hyperuricemic and xanthine oxidase inhibitory properties of tuna protein hydrolysates and its isolated fractions
# Sensory descriptive and comprehensive GC–MS as suitable tools to characterize the effects of alternative winemaking procedures on wine aroma. Part I: BRS Carmem and BRS Violeta
# Kinetics of lipid oxidation in omega fatty acids rich blends of sunflower and sesame oils using Rancimat
# Encapsulation of grape seed phenolic-rich extract within W/O/W emulsions stabilized with complexed biopolymers: Evaluation of their stability and release
# Evaluation of near-infrared (NIR) and Fourier transform mid-infrared (ATR-FT/MIR) spectroscopy techniques combined with chemometrics for the determination of crude protein and intestinal protein digestibility of wheat
# Impact of consumer behavior on furan and furan-derivative exposure during coffee consumption. A comparison between brewing methods and drinking preferences
# Effects of heat-moisture treatment after citric acid esterification on structural properties and digestibility of wheat starch, A- and B-type starch granules
# Glycine betaine reduces chilling injury in peach fruit by enhancing phenolic and sugar metabolisms
# Effects of skim milk pre-acidification and retentate pH-restoration on spray-drying performance, physico-chemical and functional properties of milk protein concentrates
# Simultaneous determination and risk assessment of fipronil and its metabolites in sugarcane, using GC-ECD and confirmation by GC-MS/MS
# Extraction of lycopene using a lecithin-based olive oil microemulsion
# Discrimination of geographical origins of Chinese acacia honey using complex 13C/12C, oligosaccharides and polyphenols
# β-Agarase immobilized on tannic acid-modified Fe3O4 nanoparticles for efficient preparation of bioactive neoagaro-oligosaccharide
# Influence of fried food and oil type on the distribution of polar compounds in discarded oil during restaurant deep frying
# Structural elucidation of fucoidan from Cladosiphon okamuranus (Okinawa mozuku)
# Determination of lipophilic marine toxins in fresh and processed shellfish using modified QuEChERS and ultra-high-performance liquid chromatography–tandem mass spectrometry
# Discrimination of Brazilian lager beer by 1H NMR spectroscopy combined with chemometrics 
# Synergistic effect of mixture of two proline-rich-protein salivary families (aPRP and bPRP) on the interaction with wine flavanols
# Impact of a post-fermentative maceration with overripe seeds on the color stability of red wines
# Inhibitory effects of dietary soy isoflavone and gut microbiota on contact hypersensitivity in mice
# Metabolite characterization of powdered fruits and leaves from Adansonia digitata L. (baobab): A multi-methodological approach
# Isolation of antioxidative compounds from Micromelum minutum guided by preparative thin layer chromatography-2,2-diphenyl-1-picrylhydrazyl (PTLC-DPPH) bioautography method
# Effect of guar gum on the physicochemical properties and in vitro digestibility of lotus seed starch
# Preparation of an intelligent pH film based on biodegradable polymers and roselle anthocyanins for monitoring pork freshness
# Extraction, structural characterization and stability of polyhydroxylated naphthoquinones from shell and spine of New Zealand sea urchin (Evechinus chloroticus)
# A review of microencapsulation methods for food antioxidants: Principles, advantages, drawbacks and applications
# Transcriptome and proteome analyses of the molecular mechanisms associated with coix seed nutritional quality in the process of breeding
# The synthesis and characterization of a xanthan gum-acrylamide-trimethylolpropane triglycidyl ether hydrogel



Vous avez vu beaucoup de science, vous ?