Molecular Gastronomy: Exploring the Science of Flavor (2 page)

Hervé This traces the search for glutamate receptors, which led to a mole-

cule that university researchers called a metabotropic glutamate receptor. That

sounds intimidating! But as I read, This’s narrative style took me out of the

specialized language of a laboratory I would never dare to enter and into the

excitement of scientific understanding of the molecular activity and interaction

of the tongue’s taste buds and the nose’s sensors.

Molecular gastronomy is not a media-driven gimmick; This calls whatever

pretentiousness resides therein the necessary price of precision.

Historically, molecular gastronomy is the consequence of the linkage of

gastronomy to science in the title and content of Jean-Anthelme Brillat-Sava-

rin’s
Physiology of Taste
(1825), made available to us in the splendid translation

by M. F. K. Fisher. The science of food, which Brillat-Savarin called gastron-

omy, was initiated earlier by chemists in the Age of Enlightenment, the late

seventeenth and eighteenth centuries, and belongs to the history of science.

The kitchen was a laboratory like any other for famous doctor and pioneering

chemist Antoine-Laurent Lavoisier. In Germany, Justus von Liebig, working

in the Age of Positivism, applied meat extracts to the soups that still bear his

name. The test tubes were pots and pans.

Brillat-Savarin called himself “le professeur.” Defining gastronomy as the

intelligent knowledge of whatever concerns nourishment, the gourmet pro-

fessor initiates his readers into a veritable eighteenth-century encyclopedia of

natural history, physics, chemistry, cookery, business, and political economy.

Hervé This, our new millennium initiator, is more rigorously focused: Mo-

lecular gastronomy deals with culinary transformations and the sensory phe-

nomena associated with eating. As a guide he achieves exemplary clarity for

the nonscientist reader, and he is consistently entertaining.

a l b e r t s o n n e n f e l d

Preface
| xi

t h e t i t l e i g a v e t h e o r i g i n a l edition of this book was
Casseroles et

éprouvettes:
saucepans and test tubes. Not the sorts of thing one normally ex-

pects to find together, either in the kitchen or the laboratory—or so it seemed

before the creation of a new scientific discipline called molecular gastronomy.

I should perhaps say a word or two about the origin of the name.

In 1988 the Oxford physicist Nicholas Kurti and I were preparing the first

of a series of international workshops on the physical and chemical aspects of

cooking, and we realized we needed a pithy phrase that would describe this

new field of research. Brillat-Savarin’s classic definition of gastronomy in the

Physiology of Taste
(1825) naturally came to mind:

Gastronomy is the intelligent knowledge of whatever concerns man’s nourishment.

Its purpose is to watch over his conservation by suggesting the best possible suste-

nance for him.

It arrives at this goal by directing, according to certain principles, all men who hunt,

supply, or prepare whatever can be made into food… .

Gastronomy is a part of:

Natural history, by its classification of alimentary substances;

Physics, because of the examination of the composition and quality of these sub-

stances;

Chemistry, by the various analyses and catalyses to which it subjects them;

| 1

Cookery, because of the art of adapting dishes and making them pleasant to the taste;

Business, by the seeking out of methods of buying as cheaply as possible what is need-

ed, and of selling most advantageously what can be produced for sale;

Finally, political economy, because of the sources of revenue which gastronomy creates

and the means of exchange which it establishes between nations.

( m e d i t a t i o n 3 , § 1 8 )

In this view, the humble hard-boiled egg belongs every bit as much to gas-

tronomy as a wonderfully complicated dish such as the one Brillat-Savarin in-

vented in honor of his mother,
Oreiller de la Belle Aurore
, a kind of pillow made

of puff pastry and stuffed with seven kinds of wild game as well as foie gras

and truffles. In both cases “intelligent knowledge”—that is, rational or analyti-

cal understanding—is needed, but it must be admitted that understanding the

scientific principles of boiling an egg will be more useful to many more people.

If all you have to eat is an egg, you had better know how to cook it properly.

So we had one part of the name we were looking for. But what kind of gas-

tronomy? The term “molecular” was very fashionable at the time (molecular

biology, molecular embryology, and so on), but it was also indispensable if

we were to limit the scope of our enterprise. I proposed that we call our field

simply molecular gastronomy, but Nicholas thought that “molecular” would

too narrowly identify it with chemistry and suggested “molecular and physical

gastronomy” instead. We started out calling it by this name, but after a while

it seemed too cumbersome. Because the analysis of the structure and behavior

of molecules obviously involves a certain amount of physics, after Nicholas’s

death in 1998 I decided to revert to the shorter form in announcing our work-

shops, which now meet every two or three years in Sicily. And so molecular

gastronomy it has been ever since.

But why not “molecular cooking”? Because cooking is a craft, an art—not

a science. Nor is molecular gastronomy the same thing as the technology of

cooking, because science is not technology. Furthermore, gastronomy seeks

to answer a wider range of questions. For example, why does a tannic wine

have a disagreeable taste if one drinks it in the company of salad that has been

tossed with an acidic dressing? This question has nothing to do with cooking

and everything to do with gastronomy.

What exactly does molecular gastronomy deal with? And how does it differ

from the well-established field of food science? Some historical perspective will

2 | introduc tion

be useful in answering these questions, but generally speaking it is correct to

say that food science deals with the composition and structure of food, and

molecular gastronomy deals with culinary transformations and the sensory

phenomena associated with eating.

Let’s begin by going back to ancient Egypt. When the anonymous author

of the London Papyrus used a scale to determine whether fermented meat

was lighter than fresh meat, was he doing an early form of molecular gas-

tronomy or of food science? It depends on what the motivation for the experi-

ment was. If he wanted to understand an effect of cooking, it was molecular

gastronomy. If he was interested mainly in the properties of meat, then it was

food science.

The succeeding centuries witnessed the development of chemistry. For a

long time it resembled cooking and used many of the same techniques: cut-

ting, grinding, heating, macerating, and so on. In the late fifteenth century Bar-

tholemeo Sacchi, author (under the pen name of Platina) of a cookbook titled

De honesta voluptate et valetudine
(1475), made little if any distinction between

chemistry, medicine, and cooking. More than 250 years later one finds much

the same state of affairs in
La suite des dons de Comus
(1742) by François Marin.

Note, however, that in the interval the French physician and inventor Denis

Papin (1647–1712) had built a pressure cooker in order to recover the substance

of bones in broth, hence the name of his machine: the digestor.

Marin’s views echoed those of Sacchi. “The science of cooking,” he wrote,

“involves decomposing, digesting, and extracting the quintessence of meats,

drawing from them their light and nutritive juices. Indeed this kind of chemi-

cal analysis is the main object of our art.” Chemical analysis! We need first of

all to make a clear distinction between art, technology, and science. To ride

a bicycle, for example, one has to push the pedals forward; this is a matter

of technique, or art. If someone were to inquire into the difference between

pedaling with the front of the foot instead of the heel, this would be a question

of technology (which, as the Greek word indicates, is the systematic treatment

of
techne
—art, craft, or skill). And if someone were to survey the surrounding

landscape while pedaling a bicycle—say, in order to avoid having to climb a

mountain—this would be an example of scientific investigation (or, more gen-

erally, the attempt to discover the mechanisms of natural phenomena).

Plainly, then, cooking is not the same thing as molecular gastronomy, for

craft aims at the production of goods, not of knowledge. For the same reason

Introduction
| 3

molecular gastronomy is no substitute for cooking because it seeks to produce

something entirely different. Marin was wrong, then, in saying that cooking is

a form of chemical analysis. Similarly, Papin’s digestor was an achievement of

technology rather than of science.

Let’s return to the eighteenth century. In 1773 French chemist Antoine

Baumé (1728–1804) devised a “recipe” for preparing “dry stocks for times of

war, or stock tablets.” In order to improve the extraction of organic compounds

he recommended boiling meats again, after the first extraction, then clarifying

the stock with egg whites and allowing the liquid to evaporate in a bain-marie

until only “perfectly dry and brittle” tablets remained. The whole problem of

making stocks and meat extracts was a very important one at a time when

neither refrigerators nor freezers existed to preserve food. But there were also

financial considerations. It is often forgotten that the great Lavoisier himself

took an interest in the confection of stocks. As
fermier général
, responsible for

collecting taxes and supplying the hospitals of Paris with food, he understood

that it was not the water in a broth that provided nourishment but the mat-

ter that had been extracted from the meat and that had undergone chemical

reaction in the course of cooking. He therefore devised a densitometer to de-

termine how much meat was necessary to feed the indigent patients of the

hospitals.

Three years later, Benjamin Thompson (1753–1814), later Count Rumford

(later still he married Lavoisier’s widow), published a 400-page book titled
On

the Construction of Kitchen Fireplaces and Kitchen Utensils Together with Remarks

and Observations Relating to the Various Processes of Cookery and Proposals for

Improving That Most Useful Art
(1776). Rumford did a great deal of work related

to food and perhaps should be considered one of the most important figures

in the prehistory of molecular gastronomy, as he was interested not only in

technology but also in science. It is even said that he discovered fluid convec-

tion while eating a thick soup whose viscosity prevented the inner layer from

cooling, thus causing him to burn his mouth.

Also during this period Antoine-Augustin Parmentier (1737–1813), a phar-

macist who had an interest in food, sought to win acceptance for the potato

in France and made a study of the flours used to make bread. Parmentier’s

fame came to be widespread in his native land, which probably explains why

A. Viard wrote in
Le cuisinier impérial, ou l’art de faire la cuisine et la pâtisserie

4 | introduc tion

pour toutes les fortunes
(1806), “All the arts and sciences have made enormous

advances in the last one hundred years, especially chemistry, which has pro-

gressed so much that a student familiar with [recent] discoveries about flavor

can demonstrate theories whose existence was not previously suspected. It is

natural, in these conditions, that cooking, which is a kind of chemistry, ad-

vanced at the same pace.” Again one sees the confusion between chemistry, a

science, and cooking, an art or craft. The definition of artists as inspired crafts-

men (proposed by Walter Gropius, founder of the Bauhaus school of design in

Weimar Germany) is worth keeping in mind.

Another German, Justus von Liebig (1803–1873), who devoted much of his

later scientific career to the analysis of food, made a fortune from an epony-

mous American company that produced meat extracts from surplus supplies

of meat. The chemical theory underlying the product turned out to be wrong,

but Liebig’s extract became famous throughout the world.

A more important result was obtained shortly afterward by the French

chemist Michel-Eugène Chevreul (1786–1889), who analyzed fats and dis-

covered their chemical structure. Also during this period, in Germany, Emil

Fischer (1852–1919) was studying sugars, again with significant consequences