BEVERAGES 119 



H 2 S0 4 . The new residue, treated with 2 per cent NaOH 

 and then weak HC1, and filtered, gives " insoluble fibre. " 

 Adulterants. Potassium carbonate, ground cocoa-shells, 

 red sanders wood, iron oxide, sugar, and starch. Micro- 

 scopic examination detects most of these. 



Paraguay Tea, known as " mate," contains 1 per 

 cent of theine. Used in South America. 



Guarana contains 5 per cent of theine or caffeine. Used 

 for migraine. From seeds. 



Kola. From the seeds of a tree growing wild on the 

 West Coast of Africa. It contains 2-42 per cent of caffeine, 

 little fat (o-68 per cent), starch and sugar 36-5 per cent, and 

 proteins 6-7 per cent. Spurious kola nuts containing no 

 caffeine are much sold. 



Coca. From the leaves of Erythroxylon coca ; contains 

 the alkaloid cocaine. The reputed sustaining powers of 

 coca leaves are not marked in the case of Europeans, 

 probably from their ordinary dietary being rich in 

 stimulant extractives of the xanthin group. On the 

 natives the effects are notable. 



LEMON JUICE AND LIME JUICE. 



Lemon Juice Is the expressed juice of the Citrus 

 limonum, and is a slightly turbid, yellowish liquid, with a 

 sharply acid taste. The British Pharmacopoeia standard 

 is : specific gravity, 1030 to 1040 ; citric acid, 30 to 40 grains 

 per fluid ounce ; and ash, not more than 3 per cent. The 

 Board of Trade standard for lemon and lime juices is : 

 sp. gr. (when de-alcoholized) 1030, and 30 grains per 

 ounce of citric acid. As found in the Merchant Service, 

 or in the Royal Navy, these juices have sugar added to 

 them, and have 1 ounce of brandy added per 10 ounces of 

 juice, or are pasteurized at 145 F., or are boiled. The 

 alcoholic juice keeps better, and freezes at a lower tem- 

 perature. The latter point is of importance in Arctic 

 and Antarctic expeditions. Good juice keeps about three 

 years ; bad juice becomes turbid, stringy, and muci- 

 laginous ; glucose and CO 2 being formed from the decom- 

 position of the citric and malic acids present. One ounce 



