646 



Messrs. Harden and Norris. Fermentation of [July 18, 



Kahlbaum's galactose was used and the last traces of glucose removed by 

 fermentation with ordinary brewers' yeast. The experiments were all 

 carried out at 25°, those with yeast-juice being performed in the presence of 

 toluene. 



I. Action of Untrained S. Carlsherg I on Galactose and Glucose. 



For this experiment wort cultures were employed and quantities of 

 1 gramme of the yeast were incubated with sohitions of galactose and 

 glucose and with water, the volume being the same in each case. The 

 galactose was not fermented at all. 



Table I. — Untrained S. Carlsherg I on Galactose and Glucose. 



Experiment. 



Time, 

 in minutes. 



Total fermentation. C.c. of COj evolved in the time given. 



Galactose. 



Glucose. 



Autofermentation. 



1 

 2 



65 



35 



2-5 

 1 -2 



52 -9 



2-4 



1 -3 



II. Fermentation of Galactose and Glucose hy S. Carlsherg 1 groivn in a Medium 

 containing Hydrolysed Lactose. 



The results tabulated below show that the ratio of the rates of fermenta- 

 tion of these two sugars varies between wide limits. The conditions 

 controlling this have not yet been ascertained. 



Table II.— Comparison of Rates of Fermentation of Galactose and Glucose by 

 S. Carlsherg I after Cultivation in a Medium containing Hydrolysed 

 Lactose. 



Experiment. 



3 

 4 

 5 

 6 

 7 

 H 

 9 

 ]0 

 H 



Mean rate of fermentation for 30 minutes. 

 C.c. of COj evolved in 5 minutes. 



Galactose. 



Glucose. 



2-81 

 10 -21 



•52 

 •52 

 •00 

 •65 

 •37 

 •70 

 •35 



2- 35 

 19 -25 



2 -32 



3- 52 

 6 -63 



2 -18 



3 -50 

 7-60 



15 •OO 



Ratio 



Glucose 



Galactose 



0-84 

 1 -86 

 1 ^52 



1 -SQ 

 1 -05 



1 -31 

 2^55 



2 •S-.i 

 2-79 



