CHAPTER XIX. 



MOLASSES. 



Geerligs' Theory of Molasses.* The chief factor in the 

 formation of molasses was formerly considered to be the viscidity of the 

 syrups preventing free movement of the sugar molecules ; this theory fitted in 

 with the knowledge that in heet molasses the sugar content was higher than 

 in a saturated aqueous solution containing the same amount of water; in 

 cane molasses the reverse is generally the case. This observation is alone 

 sufficient to invalidate the older theory, known as the mechanical theory of 

 the formation of the molasses. The whole subject has been the object of a 

 classical research by Geerligs 1 . 



Geerligs introduces his subject by a discussion of the methods of analysis 

 of molasses, and shows 



1. The method of direct polarization gives results that may be too high 

 or too low. 



2. Clerget's method gives results agreeable with those obtained by deter- 

 minations of glucose before and after inversion. 



3. The glucose present has a lower levo-rotation than that due to pure 

 invert sugar. 



4. The glucose present is not inactive at 88 C., the temperature at which 

 the activity of invert sugar vanishes. 



Of earlier experimenters Gerard and Laborde 2 and also Miintz and Hulze 3 

 found glucose from cane sugar inactive ; Gunning 4 and Meissl 5 found the 

 rotation of glucose in cane molasses the same as for invert sugar. 



Herzfeld 6 and Wehne 7 found the glucose to consist of varying quantities 

 of dextrose and levulose. The last result is the one to which Geerligs came ; 

 in his results it is always the dextrose which is present in the greater propor- 

 tion, and accordingly it is quite possible for the mixture to be optically 

 inactive. After having made complete analyses of a number of molasses, 



* When "Sugar and the Sugar Cane" was published, Geerligs' theory was only to be found 

 described in journals ; since then he has detailed his theory in his treatise 'Cane Sugar and its 

 Manufacture ' to which reference may be made for a complete account. 



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