428 



CONDIMENTS. 



Maize contains three globulins, several albumins, and a proteid zein soluble 



in alcohol. 



Potatoes contain from 70 to 81 per cent, of water. In the juicy cellular 



tissue, which yields an acid reaction when fresh, from the presence of phos- 

 phoric, malic and hydrochloric 

 acids, there is present from 16 

 to 23 per cent, of starch, 2.5 

 per cent, of dissolved prpteids, 

 consisting of one globulin (tu- 

 berin), soluble in potato-juice, 

 and some albumin, together 

 with a trace of asparagin. 

 The cell-capsules become swol- 

 len when boiled, and are 

 changed by dilute acids into 

 sugar and gum. The "eyes" 

 contain the poisonous sub- 

 stance solanin. One hundred 

 parts of potato-ash contain: 

 potassium carbonate 46.96, so- 

 dium chlorid 2.41, potassium 

 chlorid 8.1 1, magnesia 13.58, 

 calcium 3.35, phosphoric acid 

 11.91, sulphuric acid, derived 

 from burned albuminates, 6.50, 

 silica 7.17. 



Fruits contain as the prin- 

 cipal food-constituents sugar 

 and salts. Their characteristic 

 taste is due to the organic acids. 

 The gelatinizing substance of 

 fruit-jellies is the soluble so- 

 called pectin (CgjH^Og;;) , which 

 can also be obtained artifici- 

 ally by cooking from the pec- 

 tose of unripe fruit, which 

 is soluble with difficulty, and 

 from carrots. 

 Green vegetables are especially rich in salts that resemble the salts in the blood. 



For instance, unseasoned lettuce contains 23 per cent, of salts, spinach much 



iron. Of less importance in them are starch, dextrin, sugars and small amounts 



of albumin. 



FIG. 139. Section through Potato: k, cork; pi, plasma-containing 

 cells, with small starch-granules; cr, protein crystalloid; s, 

 starch. 



CONDIMENTS. 

 COFFEE, TEA, CHOCOLATE, ALCOHOLIC DRINKS AND SPICES. 



Since the time of v. Bibra the term condiment has been applied to such articles 

 of food as are used less because of their direct nutritive properties, than because 

 of their agreeable action and stimulation, in part upon the organs of taste and in 

 part also upon the nervous system. Coffee, tea and chocolate are prepared as 

 infusions or decoctions of the familiar vegetables. They contain respectively 

 an active constituent, caffein or thein (C 8 H 10 N 4 O 2 + H 2 O trimethylxanthin) 

 or the closely related theobromin (C 7 H 8 N 4 O 2 dimethylxanthin) , which are classi- 

 fied among the alkaloids, or vegetable bases. These have recently been prepared 

 artificially from xanthin. 



These alkaloids and similar bodies in many other plants are present in the 

 plants preformed. Their behavior is similar to that of ammonia. They have 

 an alkaline reaction and with acids form crystalline, well-defined salts. All 

 of these vegetable bases affect the nervous system, some feebly, as the preceding, 

 or more actively stimulating, as quinin; others have a more powerful stimulating 

 effect, to the point of paralysis, including active poisons, such as morphin, atropin, 

 strychnin, curarin, nicotin, etc. 



The alkaloids of coffee, tea and chocolate confer upon the infusions of these 

 substances generally used as popular beverages the pleasantly stimulating effect 

 upon the nervous system, refreshing the mind, animating movement and stimu- 



