The Manufacture of Food 35 



C6H12O6+C6H12O6 — ^ C12H00O11+ H2O, 



glucose + fructose — >■ cane sugar + water, 



one molecule of water being lost in the process. Cane sugar may 

 be split into glucose and fructose by heating it in dilute sulfuric 

 acid for a few minutes. This brings about the addition of a 

 molecule of water (by hydrolysis) and the subsequent splitting : 



C12H22O11 + H2O — >■ C6H12O6 + C6H12O6 



cane sugar + water — >- glucose + fructose 



The starches and celluloses are formed by combining many mole- 

 cules of the simple sugars and removing a molecule of water for 

 each molecule that enters into the combination : 



n(C6Hi206) — ^ (CeHioOs)^ + n(H20) ■ 

 glucose starch + water 



Consequently their formulas are (CeHioOs)^, in which n represents 

 a rather large number. The starches and celluloses may also be 

 split up into simple sugars by adding the required number of 

 molecules of water. This last process is the one by which corn 

 sirup (glucose) is made from corn starch. Corn starch is hydro- 

 lyzed in the same way as cane sugar, mentioned above, with the 

 result that it breaks down into glucose. The process may be 

 represented by the equation, 



(C6Hio05)n + n(H20)— >n(C6Hi206) 

 starch water glucose 



Those sugars like glucose, which are the first abundant products 

 of photosynthesis, contain six atoms of carbon, twelve atoms of 

 hydrogen, and six atoms of oxygen in each molecule. For every 

 molecule of glucose manufactured, therefore, it would require 

 six molecules of carbon dioxide to furnish the carbon and six 

 molecules of water to provide the hydrogen. These amounts of 

 water and carbon dioxide, however, contain eighteen atoms of 

 oxygen, twelve more than are needed for the making of glucose, 

 6CO2 + 6H2O — >■ C6H12O6 + 602 



We should, therefore, expect oxygen to be given off from leaves 



