Page:Popular Science Monthly Volume 23.djvu/529

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THE CHEMISTRY OF COOKERY.

the meat, keeping it below the cooking-point. If the air be heated above this, the evaporation will go on with proportionate rapidity, and as nearly one thousand degrees of heat are lost as temperature, and converted into expansive force whenever and wherever evaporation of water occurs, the film of hot, dry air touching the meat is cooled by this evaporation, and sinks immediately, to be replaced by a rising film of lighter, hotter, and drier air, which drinks in more vapor, cools and sinks, to give place to another, and so on till the inner juices gradually ooze between the fibers to the porous surface, where they are carried away by the hot, dry air, and a hard, leathery, unmasticable mass of desiccated gelatine, albumen, fibrin, etc., is produced, which, if given to a dog for the purpose of watching its effect on the animal, would render an unlicensed experimenter liable to prosecution under the vivisection act.

Now, let us suppose a similar beefsteak to be cooked by radiant heat, with the least possible co-operation of convection.

To effect this, our source of heat must be a good radiator. Glowing solids are better radiators than ordinary flames; therefore coke, or charcoal, or ordinary coal, after its bituminous matter has done its flaming, should be used, and the steak or chop may be placed in front or above a surface of such glowing carbon. In ordinary domestic practice it is placed on a gridiron above the coal, and therefore I will consider this case first.

The object to be attained is to raise the juices of the meat throughout to about the temperature of 180° Fahr. as quickly as possible, in order that the cookery may be completed before the water of these juices shall have had time to evaporate to any considerable extent; therefore the meat should be placed as near to the surface of the glowing carbon as possible. But the practical housewife will say that, if placed within two or three inches, some of the fat will be melted and burn, and then the steak will be smoked.

Now, here we require a little more chemistry. There is smoking and smoking—smoking that produces a detestable flavor, and smoking that does no mischief at all beyond appearances. The flame of an ordinary coal-fire is due to the distillation and combustion of tarry vapors. If such a flame strikes a comparatively cool surface like that of the meat, it will condense and deposit thereon a film of crude coal-tar and coal-naphtha, most nauseous and rather mischievous; but, if the flame be that which is caused by the combustion of its own fat, the deposit on a mutton-chop will be a little mutton-oil, on a beefsteak a little beef-oil, more or less blackened by mutton-carbon or beef-carbon. But these oils and carbons have no other flavor than that of cooked mutton and cooked beef; therefore they are perfectly innocent, in spite of their guilty black appearances.

If any of my readers are skeptical, let them appeal to experiment, by putting a mutton-chop to the torture, and taking its own confes-