EXPERIMENT STATION BULLETINS. 



461 



TABLE VIII. — Development of Strain II After Neuti'alization. 



The counts show no "Teat difference before and after neutralization. 



The actual figures are 



before \ 1^570,000,000 

 oeiore | i 730^000,000 



.( 1,690,000,000 

 ^"^^ ( 1,860,000,000 



B. 



790,000,000 

 950,000,000 



1,160,000.000 

 1,220,000,000 



The fermenting capacity in the first four hours is a little, but not 

 much, lower than in the preceding experiment carried on with the 

 same strain. 



The bacteria multiplied again after neutralization, approximately 

 doubling their number. The final acidity is lower than that of the 

 fresh culture. It may be mentioned that the milk was not curdled after 

 8 hours, though enough acid was formed to curdle normal milk; curd 

 was formed after 24 hours. 



The faet that the bacteria fermented and multiplied again after 

 neutralization of the soured milk made it seem worth while to try the 

 effect (of repeated neutralization. The following two tables give dupli- 

 cate experiments with two different strains of lactic bacteria, Strain II 

 and Strain IV. For these data I am obliged to Mr. L. R. Himmel- 

 berger. 



There is a great difference in the effect of neutralization upon these 

 two strains of lactic bacteria. Bacterium II increases decidedly after 

 the first neutralization ,and reaches its maximum number after the 

 third neutralization. The number is then constant until a total of 

 about 340° of acid has been foi-med. After that, the number drops 

 rapidly, and at the same time the acidity increases very slowly. The 

 cells probably by this time are injured S|0 much by the exposure to 

 sodium lactate that they die. The total amount of acid produced is 

 366° and 357° respectively. 



