THE ALCOHOL INDUSTRY. PART I. 



177 



fermentations have about the same properties as those which Spencer ^' 

 describes as occurring in sugar-cane juices. 



Viscous fermentation. — "Tlie solution becomes tliick, slimy, and ropy; and 

 starchy matters and sugar are transformed into gummy substances. This fermen- 

 tation takes place spontaneously. Small quantities of carbonic acid and hydrogen 

 are liberated." 



Putrid fermentation. — "The solution becomes turbid and viscous; ammonia is 

 set free, and a sediment deposits. The fetid odor is repulsive." 



The only changes in the sap which were investigated are the inversion 

 of the sucrose, and the alcoholic and acetic fermentations as they progress 

 spontaneously. The only control of the fermentations attempted was for 

 the pui-pose of inhibiting all changes to preserve samples for analyses 

 and for the manufacture of sugar. 



Inversion of the sucrose. — The sucrose begins to invert in about five 

 hours and the process is complete in about thirty. Three samples col- 

 lected on three different days gave the following results: 



Table XXV. — Spontaneous inversion of the sucrose of the sap. 



Time 

 interval. 



Direct polarization. 



Per cent 

 of inver- 

 sion, 

 approx- 

 imate. 



Aug. 

 19, 1910. 



Aug. 23. 



Nov. 3. 



. Hours. 

 1.0 

 1.5 

 2. 



2.5 



3.0 



3.5 



4. 



4.5 



5. 



5.5 



6.5 



7.0 



7.5 



8.0 



8.5 



9.0 



9.5 



10.0 



U.O 



12.0 



13.0 



18.0 



20.0 



22.0 



24.0 



26.0 



28.0 



30.0 



30.5 







+9.6 



0.0 



0.0 



0.0 



0.0 



0.0 



0.0 



0.0 



0.0 



0.0 



10.5 



17.5 



2.Jf 



21.0 



4.2 



28.1 



29.0 



38.6 



38.6 



3S.3 



44.3 



64.9 



61.4 



69.5 



80.0 



87.6 



91.7 



96.9 



100.0 



100.0 





+:o.6 



-rll.S 





+10.6 

 +10.6 









+9.6 



+11.5 

 -Ml. 5 





+10.6 





+9.6 



+10. 2 

 +9.4 









+9.4 



— — 



+9.0 





+9.2 





+8.2 





+6.8 





+7.0 

 +7.0 









+6.4 

 +5.4 

 +3.4 











-t-4.6 

 +3.6 

 +2.4 















+1.2 

 +0.8 

 +0.3 

 -0.1 











-0.3 





-0.8 







"A Hand Book for Cane Sugar Manufacturers, New York (1906), 228. 



