Volume 2

The practical grocer : a manual and guide for the grocer, the provision merchant, and allied trades / by W.H. Simmonds ; with contributions by specialists, trade experts, and members of the trades ; illustrated by a series of separately-printed plates.

  • Simmonds, W. H.
Date:
1904
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: The practical grocer : a manual and guide for the grocer, the provision merchant, and allied trades / by W.H. Simmonds ; with contributions by specialists, trade experts, and members of the trades ; illustrated by a series of separately-printed plates. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

    98/344 (page 70)
    ANALYSES OF COFFEE Mocha. East Indian. Raw. Roasted. Raw. Roasted. Per Cent. Per Cent. Per Cent. Per Cent. Caffeine 1.1 0.8 i.i I.O Sugar 9.6 0.4 8.9 0.4 Caffeic Acid 8-5 4-7 9.6 4-5 Fat and Oil 12.6 13.6 11.8 13-4 Albumen or Legumin ... 9.9 II.2 11.2 I3-I Alcohol extract, containing nitrogenous) and colouring matter ... j 6.9 14.1 4-3 12.7 Dextrin ... 0.9 1.2 0.8 1.4 Cellulose and insoluble colouring matter 38.0 48.6 38.6 47-4 Ash 3-7 4.6 4.0 4.9 Moisture 8.8 0,8 9-7 1.2 100.0 100.0 100.0 100.0 A slight loss of caffeine during roasting is shown by the above figures. From other experiments which have been made, however, it appears that this loss is generally very small if the roasting is properly carried out. Besides the expulsion of water, the principal changes during roasting are shown by these analyses to be the almost complete elimination of the sugar and the diminution of the caffeic acid. The saccharine matter is converted into caramel by the heat, and about one-half of the caffeic acid is altered during the development of the aroma. These altered products go to increase the quantities shown opposite “colouring matter” in the analyses. As regards the significance of the constituents of coffee from the dietetic point of view, it may be remarked that the ingredients of chief physiological importance are the alkaloid caffeine and the foodstuffs—namely, the saccharine matters, fat, and legumin or soluble albumen. It is in the presence of these last three nutritive substances, and in the practical absence of tannin, that coffee differs from tea as an article of diet. The principal substances which at one time or other have been used for mixing with or adulterating coffee are:—(i) Roots, Adulterants such as chicory, dandelion, mangold-wurzel, turnips, of Coffee, parsnips, and carrots. (2) Seeds, such as beans, peas, date-stones, acorns, malt, rye, &c. (3) Miscellaneous articles, such