THE STORAGE OF FOOD-RESERVES 151 
Accessory Food-Products.—We eat and drink many sub- 
stances derived from plants which are not strictly food at 
all. They are either consumed as aids to digestion, or, 
because of their stimulating properties, they are employed 
in the preparation of beverages. Others act medicinally 
as drugs : 
(a) Spices and Condiments.—These have little or no 
actual food-value. They serve merely to stimulate 
appetite or to render food more pleasing. The principles 
contained in them arise as the result of certain chemical 
changes taking place within the plant, and, most probably, 
in connection with the respiratory functions. Respiration 
begins with the inception of oxygen, and usually termi- 
nates with the elimination of carbonic acid gas. If the 
process is interfered with in any way, organic by-products 
are formed, and if these turn out to be useful to the plant, 
their formation tends to become habitual, and the dis- 
position to produce them becomes hereditary. 
These substances are found in mustard (ground seeds of 
Brassica nigra), pepper (ground fruits of Piper nigrum), 
ginger (rhizomes of Zingiber officinale), cloves (dried 
flower-buds of Eugenia caryophyllata), nutmeg (seed of 
Myristica fragrans), capers (flower-buds of Capparis 
spinosa), chillies (fruits of Capsicum annuum), water- 
cress (shoots of Nasturtium officinale), horse-radish (rhi- 
zome of Cochlearia Armoracia). 
The bases of flavourings are volatile oils. They are 
generally obtained by distilling the parts of the plants 
where they are present with water—e.g., aniseed, caraway, 
lavender, cloves, peppermint, rosemary, chamomile, 
cinnamon, and lemon. The chemical composition of 
some of these oils is known, and they can be artificially 
prepared in the laboratory. 
(6) Beverages.—Infusions of tea, coffee, and cocoa are 
universally used as beverages. Alcohol is obtained by 
fermenting sugar with yeast, either directly from a 
vegetable sugar, or indirectly from starch. The range of 
intoxicating drinks is almost as great as the range of man 
himself. Sugary liquids, capable of fermentation, are 
obtained from all kinds of plants—sprouting barley (beer 
and whisky), grapes (wine, brandy, liqueurs), potatoes 
(inferior spirits), sugar-cane (rum), agave (pulque), coco- 
nut (toddy, arrack), honey (mead), etc. 
