TITRATION AND ADJUSTMENT OF CULTURE MEDIA 



217 



noted in charts 1 and 2, the total acidity Unes fall into two groups 

 according to the method of titration. 



If chart 5, showing the total rises in acidity of the series B30 C, 

 B 60 C, B 120 C and the series Ba 30 C, B2 60 C, B2 120 C, were 

 applied successively to the corresponding curves of the uncor- 

 rected series in charts 1 and 2, so that the point of origin in each 

 set were the same, it would be seen that in every instance the 



7 HART ,5 



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■7^' 



/ 



./ 



y 



^ 



■^ 



r56W 



# 



■r/ 





*^ 



"'«> 



-^c* 



i^ 



560C» 





'/.f 



■^ ;- 





H=^* 



total rise of acidity of the corrected curve equals or exceeds that 

 of the uncorrected portion. 



From this it is plainly evident that, in spite of successive 

 corrections of acidity with normal sodium hydroxid, hydrolysis 

 not only continues on the application of heat but there is pro- 

 duced in meat infusion media approximately as much acidity 

 as would be developed were no correction made. 



Chart 6 shows the actual acidity of the different corrected 

 portions after the successive adjustments and periods of heat- 

 ing. As can be seen, those portions adjusted according to the 



