Culinairy Arts Blog Molecular Gastronomy. the next chapter.

Many cooking and cocting possibilities As "cooking" is a very common word, applied to diverse possibilities, a classification of possibilities isto be looked at.Some years ago, we proposed to distinguish when food is put in contact with a hot solid, a hot liquid, ahot gas, when it is heated by radiation or when it is being transformed by others processes. The liquidscan be oil or water solution, at various temperatures: for example, poaching fish means cooking meatfish in a simmering aqueous solution, i.e. at a temperature lower than 100°C. Cooking in air can bedone in many different ways: in very hot dry air, meat is "roasted"; in mildly hot air, it is smoked, ordried; in vapour, it is vapour cooked. For very long, infrared radiations were the only radiations used incooking, but, after Wold War Two, cooks began using also microwaves, or other electromagneticradiations, as these radiations deposits energy when absorbed by food.There are other possibilities than the traditional ones. Cooks did not use much "pressure cooking"(applying pressures of many thousands of atmospheres), and did not use much "chemical cookings",using acids (except in cebiche and other similar processes), alkalis (except in one century old eggs),alcohol...Moreover, these "simple processes" can be applied one after another. Assuming that we use 12 kindsof simple processes, a table of 12 by 12, i.e. 144 cells can be constructed to describe "doubleprocesses" such as braising, where the first process is cooking in very hot air, and the second processis cooking in a liquid. A large number of these cells were never explored: they are a guide to culinaryinnovations. We eat only disperse systems Let's now consider culinary activities in general, and not only cooking. It is probably very important torecognize that we do not eat liquids (we drink them) or pure solids (they are too hard): food isgenerally what are called disperse systems, whose simplest possibilities are given in the followingtable: Table 1. The simplest disperse systems (only two phases): some small structures of thephases indicated in the upper row are dispersed in the continuous phase indicated in the leftcolumn.Egg white is a solution (of proteins, about 10%, in an aqueous solution) and no disperse system, butwhipped egg whites are foams, as air bubbles are put into the liquid by the whisk. The same whippedegg whites, plus sugar, dried in the oven, make meringue, which are solid foams. Mayonnaise, with oildroplets dispersed in the water from the egg yolk (50% of an egg yolk is water) and from vinegar, areemulsions. Shallots are gels, as they are solids, but made of cells, i.e. systems containing a liquid.Meats also, are gels, as well as jams or jellies. Egg yolk is a suspension, because it is composed ofgranules dispersed in a plasma. And bread dough before fermentation is a solid suspension, becausestarch granules are dispersed into a gluten (proteins) network.However the previous table is not enough to describe the wide variety of dishes. Even egg yolks aremore complex than simple suspension of granules in a plasma, because egg yolk has also a structure,which can be seen using ultrasonic devices: they are made of concentric layers, because hensdeposits materials at different rates during days and night. One may even count the layers to knowthat the hen needs about one week to produce an egg.Potatoes, also, are more complex than shallots, as the cells, full of water, also contain starch granules.In this regard, they are suspensions dispersed in a gel!In order to describe the complex cases (the majority), let's use the abbreviations : G for gas, O for oil(by "oil", we mean any liquid fat, whatever the flavour), W for water (by "water", again, we mean anyaqueous solution), and S for solid; we use also "operators", such as "/", for "dispersed into", "+" for"dispersed in the same phase as", É for "at the centre of", and s for "lying over".The following table now indicates the "formulas" of dishes, along with their name: