“The examination of coffee,” observes Dr. F. Knapp, “has led to interesting results, although they are still defective in pointing out the quantitative composition of the berry.”
The following is the composition of the ash according to Levi:
| Potash | 50·94 |
| Soda | 14·76 |
| Lime | 4·33 |
| Magnesia | 10·90 |
| Oxide of iron | 0·66 |
| Phosphoric acid | 13·59 |
| Sulphuric acid | trace |
| Chlorine | 1·22 |
| Silicic acid | 3·58 |
| 99·98 |
According to the analysis of Payen, the unroasted coffee-berry has the following composition:
| Moisture | 12·0 | |
| Glucose and dextrine | 15·5 | |
| Nitrogenous matters | 13·0 | |
| Chlorogenate of caffeine, &c. | 3·5 to | 5·8 |
| Fatty substances | 10 to | 13·0 |
| Cellulose and woody fibre | 34·0 | |
| Mineral substances in ash | 6·7 | |
| Essential oil | ·003 | |
| 100·0 |
Or to define the per-centage more closely, we may put it thus:
| Water | 12·000 |
| Caffeine, or theine | 1·750 |
| Casein | 13·000 |
| Aromatic oil | 0·002 |
| Sugar | 6·500 |
| Gum | 9·000 |
| Fat | 12·000 |
| Potash, with a peculiar acid | 4·000 |
| Woody fibre | 35·048 |
| Mineral matter | 6·700 |
| 100·000 |
In another form this shows us:
| Water | 12·00 |
| Flesh-formers | 14·75 |
| Heat-givers | 66·25 |
| Mineral matter | 7·00 |
| 100·00 |