Molecular Gastronomy: Exploring the Science of Flavor (45 page)

that they do not contaminate the filets. After being electrically charged as they

pass under the grate, the smoke particles are impressed on the filets by a dif-

ference in electrical potential (amounting to several tens of thousands of volts)

between the conveyor belt and the grate. In this method the smoking lasts

fifteen minutes (rather than three and a half hours, as in the usual procedure)

so no additional drying out occurs.

Smoking Salmon
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The electrical system could easily be adapted to the scale of traditional smok-

ing, where up to 400 kilograms (880 pounds) of salmon filets can be treated at

a time, and the new method of salt drying and cold smoking could be applied

to various other meats and fish. Naturally, one wants to know whether products

prepared in this way are as good as the old ones. At first their coloring was a

bit more pronounced than that of smoked filets today, but by prefiltering the

smoke it became possible to give them a lighter tint. As for the flavor, it is not

noticeably different from that of salmon smoked in the traditional manner.

308 | a c uisine f or t omor r ow

93

Methods and Principles

On the invention of new recipes.

w e c o o k t o d a y t h e w a y p e o p l e c o o k e d in the Middle Ages, content

to mechanically execute fixed recipes—this at a time when space probes are

being sent to Mars. We need to ask ourselves how reflection and rationality can

be combined to renew creativity in cooking.

Certain types of cooking are pure in the sense that they involve only a single

physical phenomenon. The oldest ones are those in which heat is transmitted

through conduction. Since ancient times only the materials that transport the

heat have changed.

The first type of pure cooking consists of putting food in direct contact with

a hot solid: on stones heated by embers, for example, or on a cast iron plate

heated by fire, inside a layer of salt that is heated, or in a mold that is heated by

fire or placed in an oven (as in the cooking of custards, flans, and so on).

Heat can be transmitted by a hot liquid as well. If this liquid is boiling

water, one can use it to boil meats; if it is simmering water (or sauce), one

obtains various poached dishes (fricassees, blanquettes, matelotes, fillings for

vol-au-vents, and so on).

Cooking can also be done by means of hot air. In the case of roasting, the

air is dry and heated to a temperature greater than 100°c (212°f). In the case of

drying or smoking, the air is dry and the temperature less than 100°c (212°f).

In the case of braising, steaming, and cooking
en papillote
and
en croûte,
the

air is moist.

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table 1. double-cooking me thods

First this cooking method

Contact Simmering

Boiling

Warm,

Hot,

with

Humid

Microwave Acidification

Dry

Dry

Infrared

Solid

W

W

ater

ater

Air

Air

Air

Oil

Contact with Solid 1 2 3 4 5 6 7 8 9 10

Simmering Water

11 12 13 14 15 16 17 18 19 20

Th

Boiling Water 21 22 23 24 25 26 27 28 29 30

en

this

Warm, Dry Air 31 32 33 34 35 36 37 38 39 40

one

Hot, Dry Air 41 42 43 44 45 46 47 48 49 50

Humid Air 51 52 53 54 55 56 57 58 59 60

Oil 61 62 63 64 65 66 67 68 69 70

Infrared 71 72 73 74 75 76 77 78 79 80

Microwave 81 82 83 84 85 86 87 88 89 90

Acidification 91 92 93 94 95 96 97 98 99 100

Double-cooking methods are numerous; each cell in this table represents one possibility. For example, cell

25 represents cooking first in hot, dry air, then cooking in boiling water.

Classic French cuisine also involves the indirect transmission of heat by

means of infrared rays, most notably in the case of
rôtissage à l’ancienne
(be-

cause in true roasting the meat must be placed in front of the heat source, not

above it). A laser or, more generally, visible high-energy waves can be used for

the same purpose, with similar results. A well-known innovation that allows

heat to be transferred directly to foods is microwave cooking.

Finally, acid is used by some peoples as a medium for cooking fish, as in

Tahiti and Central and South America (seviche).

Double Cooking Methods

Classical cuisine sometimes superimposes or otherwise combines these

pure types. For example, grilled meats sometimes are the result of heating first

by radiation and then by means of a dry fluid (typically air, but in principle any

310 | a cuisine for tomorrow

other gas). Braising in the traditional style is done first by browning the outside

of meats in a hot oven and then simmering them in a liquid.

Are other combinations possible? It may be useful to follow the example

of Dimitri Mendeleev, who sought to make sense of the apparent disorder of

chemical elements by constructing a table in which elements are presented in

the order of their atomic mass in rows and grouped in columns according to

the similarity of their chemical properties. In the same spirit one can construct

a table whose entries along both rows and columns are pure types of cook-

ing. The numbered cell at the intersection of each row and column designates

the type of dish that results from first cooking a food in the manner indicated

at the head of the column and then cooking it in the manner associated with

the row.

A number of cells in this table identify familiar culinary techniques. For

example, cell 20 (acidification followed by simmering in liquid) corresponds

to the classic recipe for cooking wild boar. Cell 63 (boiling in water followed

by frying in oil) corresponds to certain recipes for French fries. Other squares

refer to unknown procedures, however. Additional lines and rows could be

incorporated to take account of novel techniques such as cooking under very

high pressures.

Expected Inventions

Surely new procedures can be invented. In certain cases the procedure sug-

gested by mechanically applying the methods indicated seems unpromising.

For example, why should cooking be done twice in contact with a solid (cell

1)? Nonetheless, the cells lying along the principal diagonal that runs from the

upper left corner to the bottom right are not uninteresting; for instance, the

two fryings associated with cell 67 correspond to the method of deep-frying

potatoes by two immersions in hot oil.

Elsewhere novel procedures must be devised. For example, cell 27 involves

frying first and then cooking in boiling water. The frying would produce a dry

and hardened surface layer in addition to specific flavors. To be sure, the sub-

sequent cooking in boiling water would destroy the crispiness achieved by this

method, but it would also redistribute the aromatic molecules created during

the first phase. The overall flavor therefore would be quite different from the

one obtained by braising.

Methods and Principles
| 311

This is only one example. Other squares suggest new possibilities and in-

vite inspired chefs to travel the paths they open up for exploration. Once these

combinations have been charted, the next task will be to construct tables in

more than two dimensions.

312 | a c uisine f or t omor r ow

94

Pure Beef

A textural additive for restructuring meats.

w h y d o t h e f r e n c h e a t l e s s b e e f than they did only ten years ago? In

part it is because the quality of the meat does not justify its high price. Tender

cuts that can be cooked rapidly (various types of steak, for example) are expen-

sive because they constitute only 20–30% of bovine muscle tissue. What can be

done with the other cuts that used to be tenderized by long, slow cooking?

The meat processing industry has proposed a solution in the form of re-

structured products such as ground beef and meats sliced into thin sheets.

Both techniques—cutting fresh meats into very small pieces and cold-hard-

ened meats into very thin slices—destroy the collagen networks that form the

majority of the muscles in the anterior half of the animal. Yet once it has been

destructured, meat must be put back together: The butcher in your super-

market reshapes ground beef with a press, for example, but there isn’t always

much left of the reformed product after cooking.

Cooks know that cooking an egg white produces a gel that can trap dis-

persed particles; this is the principle of fish loaves, clafloutis (a custard made

with cherries or plums), and quiches. Drawing on this principle in order to

restore cohesiveness to destructured meats, the processing industry has intro-

duced various textural additives with increased binding power, such as sodium

alginate, an extract of algae. However, the use of dairy and vegetable com-

pounds makes it impossible to advertise the product as pure beef.

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Many researchers have looked for ways to extract such additives from meat

itself, particularly from the scraps that remain on the bones after butcher-

ing. Teams led by Joseph Culioli and Ahmed Ouali at the Institut National

de la Recherche Agronomique (inra) stations in the Clermont-Ferrand area

have shown that, at least in the laboratory, myosin can be used as an effective

binding agent.

Myosin is an abundant protein, accounting for 20% of the dry matter in

the striated skeletal muscles that can be processed by mechanical means. Pro-

teins in the muscle mass of the animal fall into three categories: myofibrillary

proteins, sarcoplasmic proteins, and connective tissue proteins. Myosin is the

principal protein of the myofibrillary system, where it is found in the form

of thick fibers. In the presence of calcium ions and adenosine triphosphate

(atp), the fuel of living cells, these fibers combine with more delicate fibers

composed mainly of actin, giving rise to muscle contraction when the two sorts

of fiber slide past one another.

Myosin Gels

Because the properties of proteins depend on their amino acid sequences,

they do not all have the same gelatinizing effect. The thermal gelatinizing

properties of myosin, which are also involved in the preparation of cooked

hams, pâtés, sausages, and so on, are greater than those of actin. To determine

which combination of factors yields the firmest gel, the inra biologists devel-

oped new extraction methods to compare the effect of myosin proteins from

two different types of muscle (fast white muscles, which are responsible for

brief spurts of intense effort, and slow red muscles, which function in the pres-

ence of oxygen) removed from animals at different times after death. Initially

myosin was extracted from muscles in rabbits because they are unmixed, being

either red or white.

Protein samples were extracted by grinding up the muscles and then plac-

ing them in solutions with different concentrations of salt. The thermal gela-

tinization of the protein suspensions in these solutions was studied with the

aid of a rheometer (an instrument for measuring the flow of fluids), which

revealed both the viscous and elastic characteristics of the gels.

314 | a c uisine f or t omor r ow

A Hot Gel

These measurements showed that thermal gelatinization occurs even at

very weak myosin concentrations (0.1–0.5%) and that the firmness of the re-

sulting gels strongly increases with the myosin concentration.

The gelatinization of pure myosin begins at 40°c (104°f), with the rigidity

of the gels increasing up to 80°c (176°f). The purer the myosin solution, the

greater the rigidity. As with other gels, the rigidity of myosin gels depends

on the salt concentration and the acidity of its environment. The myosins

that form the firmest gels are found in the fast white muscles, with a pH of

about 5.8, and in the presence of salt, which favors the dissociation of macro-

molecular chains.

Subsequent analysis confirmed the suitability of bovine myosin for the re-