THE ALCOHOL INDUSTRY. PART I. 



125 



five minutes^ at the end of which time the fifteen tuquils, containing 1,150 

 cubic centimeters of tuba, were emptied into a glass bottle and at once 

 taken to the distillery and analyzed. The sample showed a Brix of 

 10.8 and sucrose of 7.2 per cent. The rate of inversion and alcohol and 

 acid formation were as follows: 



Table VIII. — Spontaneous fermentation of the sap collected in iamboo receptacles 

 {composite samples from fifteen plants). 



Time 



in 

 hours. 



Polariza- 

 tion. 



Alcohol. 



Acidity. 



CO ^ 

 CO. ^(,. 



As 

 acetic. 





 1 



4 



4.5 



6 



8 



8.5 

 10 

 10.5 

 23.5 

 24 

 28.5 

 48 

 49 



49.5 

 57 



+ 7.2 



0.0 

 0.0 



6.0 



0.036 



+ 6.0 







0.02 



8.0 

 14.0 



0.048 

 0.084 



+ 4.5 

 + 3.5 





0.021 



30.0 



0.180 



+ 2.5 





40.0 

 63.0 



0.240 

 0.378 



— 1.9 





2.3 



— 1.4 



0.0 



80.0 



0.480 









96.0 



0.576 





3.1 



96.0 



0.576 





A sample of tuba gathered from tuquils as ordinarily cleansed at the distillery 

 gave the following results. 



Time interval 

 (hours). 



10 



Polarization 

 -1.00 



13 



-0.7 



15 



0.0 



The rate of inversion is dependent upon so many factors which are so difficult 

 to eliminate or control that no strictly accurate methods were attempted. 



Alcoholic and acetic fermentations. — ^When the sap is collected ac- 

 cording to the native method, common to all the distillery employees 

 and tuba gatherers, the inversion is complete and the alcoholic fermen- 

 tation well under way, sometimes completed, when the sap arrives at the- 

 distillery. It is milk}^ in appearance and covered by a thick layer of 

 foam. Sometimes the acetic acid fermentation has progressed to a consid- 

 erable extent. 



