Brill and Thurlow: Alcohol from Molasses 



291 



Table XXIV. — Results for a mixture of tuba and molasses. 



Fermen- 

 tation. 



- 



Hours. 

 16 

 40 

 64 

 88 

 112 



Temper- 

 ature. 



42 

 40 

 37 

 SS 

 33 



Cell 

 count. 



74 

 54 

 50 

 48 

 43 



Alcohol 



by 

 volume. 



5.09 

 6.61 

 5.64 

 5.46 



Density. 



7.4 

 5.9 

 5.8 

 5.7 



Acidity. 



10 

 10 



11 



14.5 

 16.5 



Alcohol. 



1 



Maxi- 

 mum 

 yield. 



Yield. 

 pi;r cent 

 of theo- 

 retical. ' 



5.61 



•66.7 



















« Assuming that the sugar content is 10 per cent, which is leas than good tuba should 

 contain. 



The yield recorded in Table XXIV was somewhat less than in 

 the preceding test and is not comparable with the yield ob- 

 tained in fermenting a solution in which the temperature is kept 

 below 30° C. and vigorous clean yeast is used for inoculation. 

 The acidity of this solution increased rapidly at first, doubtless 

 owing to the activity of the peroxidase carried in the tuba. The 

 activity of the peroxidase will decline when the alcohol content 

 of the ferment increases, and this period is marked by the 

 period of no change in the acidity of the ferment, but after a 

 short interval it again increases, due to the activity of bacteria. 



The density, as shown in Tables XXII and XXIV, has not 

 decreased to the same extent as in Tables XVIII and XX. Many 

 results better than these recorded in Tables XXII and XXIV 

 are obtained by the distilleries of the Islands. The distillery 

 to which we had access has records of better yields than these, 

 but the fact that such yields occur when the "tuba has gone 

 bad," or because of other reasons, shows the need for closer 

 supervision and greater knowledge of the best conditions for 

 fermenting this molasses. 



RECOMMENDATIONS 



We recommend the sterilization of the molasses solution 

 wherever this can be attained without too great cost or the 

 installation of extra machinery. If this is impossible, the use 

 of good water for diluting the molasses to a definite density, 

 about 16.5 brix, is essential. Two grams of sulphuric acid and 

 at least 0.4 gram of ammonium sulphate to every liter of ferment 

 should be added. Inoculate the ferment with clean yeast. One 

 part of fermenting wort to 100 or 150 parts of ferment is the 

 right proportion. Seed for the production of this inoculation 



