Cocoa was introduced into Europe about one hundred years before tea and coffee were. The cocoa which is made into the beverage of the same name is made from the seeds of Theo-broma cacao. They develop in a pulpy fruit that somewhat resembles a cucumber. They are gathered into heaps in a warm, moist place and permitted to ferment. This process darkens the beans, lessens a bitter taste that they have at first, and loosens any pulp adhering to them. Afterward they are roasted in order to make them brittle and to loosen their husks. They break readily into halves called cocoa nibs. The latter contain about 50 per cent, of fat or cacao-butter, some starch and albuminous matter, but very little protein, a little cellulose, and from 1 to 3 per cent, of alkaloids and some oxalates. The active principle, theobromin or dimethylxanthin is closely related to caffein.

The beverage cocoa differs from tea and coffee in that it is nutritious as well as stimulating. Its food value is due to the fat that it contains. The starch and protein are too inconsiderable in amount to be of much worth. The beverage usually is made with milk, and sugar is added to it in varying quantities. These additions increase its nutritive properties very much. Ten grams of cocoa, the amount usually used to make a cupful, yields fifty to seventy calories. When made with milk and sugar, the beverage will yield 400 calories. The stimulating effect of theobromin, the chief alkaloid of cocoa, is different from that of caffein, to which it is chemically allied, in that it does not cause sleeplessness or muscular tremors. Under its influence the mind does not become so alert, but it relieves a feeling of muscular fatigue in much the same way. The excessive use of cocoa does not produce the nervous symptoms that tea and coffee do, though it is likely to cause indigestion because of the large amount of fat in it and sugar added to it. If the beverage is not made too rich with cocoa and not too sweet, it is digestible, somewhat nutritious, and mildly stimulating. It is much better adapted for use by children than tea or coffee, which should not be given to them at all. Cocoa cannot be used by persons who find it difficult to digest fats. It is an agreeable and useful beverage for convalescents, but can rarely be used by those whose gastric digestion is disturbed or enfeebled.

Cocoa nibs are ground, and often a part of the fat is removed from them when they are prepared for the retail market. Chocolate is cocoa to which sugar, starch, and flavoring, usually vanilla, have been added. It contains commonly more than 50 per cent, of sugar. To both cocoa and chocolate an alkali is frequently added to make them more soluble or more easily suspended in water, for cocoa goes into solution very imperfectly. The fat in it and most of the other ingredients are suspended in water or milk, whichever may be used as a vehicle. An alkali converts a little of the fat into soap, which helps to emulsify the remainder.

Cocoa is quite as quickly disposed of by the stomach as tea or coffee. Two hundred cubic centimeters, or a cupful of any one of them, disappears from the stomach in a little less than two hours if they are made with water, and in two and a half hours if cocoa is made with milk.

The following analyses of a few of the preparations of cocoa and chocolate on the market will give a better idea of their average composition.