7Ô 



Van I ter son and Miss van Amstel investigated the 

 influence of température on alcoholic fermentation and 

 on the inversion of cane-sugar '). 



The reaction-velocity of alcoholic fermentation was 

 measured by means of the amount of COj (calculated in ce.) 

 produced per second. The yeast was mixed with a certain 

 amount of water and vvarmed beforehand apart from the 

 sugar-solution. When both solutions had arrived at the 

 température of the bath they vvere mixed. After the 

 production of 25 to 30 ce. gas the further production 

 was sufficiently regular to start the observations. The 

 total amount of gas collected did not cxceed 100 ce. and 

 déterminations were made of the time needed for the 

 production of the subséquent volumes of 2, 5, 10 or 25 ce. 

 COj, the amount of each being regulated according to the 

 intensity of the gas-production. 



The reaction-velocity of alcoholic fermentation proved 

 to be independent of the time of preliminary warmingup 

 to 45° C, if this time did not exceed 20 minutes. Above 

 45° C. the influence of the time of preliminary warming 

 appeared, and the reaction-velocity diminished during the 

 experiment. 



The reaction-velocities found in this way hâve been 

 collected in the following table: 



1) Bolh processes yielded tlic eamc rcsult; as only the lirsl onc 

 has been described more fuUy, I deal with this alone. 



