---------------+-----------+-----------+-----------+----------- | Water. | Fat. | Ash. | Nitrogen. ---------------+-----------+-----------+-----------+----------- | per cent. | per cent. | per cent. | per cent. Machala | 4·97 | 47·80 | 3·88 | 2·25 Arriba | 6·57 | 47·44 | 3·52 | 2·31 Caracas | 6·00 | 46·39 | 4·19 | 2·23 Puerto Cabello | 5·71 | 48·74 | 3·94 | 2·13 Surinam | 5·01 | 46·26 | 2·99 | 2·20 Trinidad | 6·07 | 45·74 | 2·04 | 2·04 Port au Prince | 4·73 | 48·58 | 3·89 | 2·33 ---------------+-----------+-----------+-----------+----------- The most important constituents of cocoa are the fat (cocoa-butter), and the alkaloid (theobromine). _Cocoa butter_ forms a whitish solid of 0·970 specific gravity, fusing at 30°, and soluble in ether and in alcohol. _Theobromine_ (C_{7}H_{8}N_{4}O_{2}) crystallises in minute rhombic prisms, which are insoluble in benzol, but dissolve readily in boiling water and alcohol. It sublimes at 170°. Theobromine is exceedingly rich in nitrogen, containing over 20 per cent. of the element. In this and many other respects it bears a great resemblance to theine. The proportion of mineral ash in cocoa varies from 3·06 to 4·5 per cent. James Bell[16] gives the following composition of the ash of Grenada cocoa nibs:-- Per cent. Sodium chloride 0·57 Soda 0·57 Potassa 27·64 Magnesia 19·81 Lime 4·53 Alumina 0·08 Ferric oxide 0·15 Carbonic acid 2·92 Sulphuric acid 4·53 Phosphoric acid 39·20 ------ 100·00 ------ The most characteristic features of the ash of genuine cocoa are its great solubility, the small amounts of chlorine, carbonates, and soda, and the constancy of the proportion of phosphoric acid contained. Bell has also analysed several samples of commercial cocoa. The following will serve to illustrate their general composition:-- Per cent. Moisture 4·95 Fat 24·94 Starch (added) 19·19 Sugar (added) 23·03 Non-fatty cocoa 27·89 ------ 100·00 ------ Per cent. Nitrogen 2·24 Ash 1·52 Cocoa, soluble in cold water 31·66 Ash in portion soluble in cold water 1·17