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 As gluten is only very sparingly soluble in boiling water, in the usual way of making coffee the flesh-formers are thrown away with the dregs; the addition of a little soda to the water partly prevents this waste. The various components in one pound of coffee will be-- oz. grs. Water 1 407 Caffeine, or theine 122 Casein, or cheese 2 35 Aromatic oil 1½ Gum 1 192 Sugar 1 17 Fat 1 402 Potash 280 Woody fibre 5 262 Mineral matter 1 31 The part roasted is the albumen, which is of a hard, horny consistence; and Lindley remarks that it is probable that the seeds of other plants of this or the stellate order, whose albumen is of the same texture, would serve as a substitute. This would not be the case with those with fleshy albumen. Coffee loses in weight by roasting, but gains in bulk in proportion to the heat applied. Payen found the following amount of nitrogen in 100 parts dried: nitrogen. ash. Martinique 2·46 5·00 Bourbon 2·54 4·66 Mocha 2·49 7·84 The coffee from Martinique lost 11·58 per cent. of its weight by drying. This description of coffee also afforded the following results: -----------------+-------------+-------------+-------------+-------------- |Unroasted. | Slightly | Chesnut | Brown. | | reddened. | brown. | -----------------+-------------+-------------+-------------+-------------- Loss in roasting | -- | 15 per cent.| 20 per cent.| 25 per cent. Increase in bulk | -- | 1·3 times | 1·53 times | -- Extract |40 per cent. | 37 per cent.| 37·1 per ct.| 39·25 per ct. Insoluble residue|48·5 “ | -- | -- | -- -----------------+-------------+-------------+-------------+-------------- Coffee, as ordinarily prepared for beverage, contains only two-sevenths of the nitrogenous or nutritive matter of the fresh bean, but two-thirds of the roasted, and the mineral ingredients are all present.