CA RBOH YDRA TES .",.", 



are soluble in water hut insoluble in alcohol. Dextrose 

 is easily changed, or fermented, by fungi and bacteria to 

 alcohol and carbon dioxide; to lactic acid; and to butyric 

 acid, carbon dioxide, and hydrogejn. Pure dextrose can 

 be made by the hydrolysis of starch or sucrose with dilute 

 hydrochloric acid, and recrvstallization from hot alcohol. 

 Commercial glucose is made in this country by boiling 

 cornstarch under pressure with hydrochloric acid, neutral- 

 izing the acid with sodium carbonate, and clarifying the 

 liquid with bone charcoal. The product is sold as a thick, 

 amber-colored liquid containing 30 to 40 per cent, of dextrose, 

 the rest being dextrins and other impurities. By boiling the 

 mass longer more dextrins are converted to dextrose and a 

 crystallizable product containing 70 to 80 per cent, dextrose 

 is obtained. Glucose is used largely in making candy, 

 jellies, preserves, table syrup, etc. 



53. Levulose, Fructose, Fruit Sugar. — C 6 Hi20 6 , graphically: 



H 

 H— C— O— H 

 H— C— O— H 

 H— C— O— H 



H— C— O— H 



I 



c=o 



I 



H— C— O— H 



I 

 H 



This constitutes another single "sugar" group of atoms. 

 Levulose is found in plants, particularly the sweet fruits, 

 and nearly always with dextrose. Honev is almost wholly 

 a mixture of levulose and dextrose. Levulose is formed 

 naturally by the enzyme hydrolysis of sucrose, or arti- 

 ficially by hvdrolvsis of sucrose with dilute hydrochloric 

 acid. In either case there are produced equal quantities 

 of dextrose and levulose. Physiologically it probably plays 



