212 EMULSIONIZING PROPERTY OF PANCREATIC JUICE. [BOOK II. 



Upon what Claude Bernard was led to believe that the pro- 

 does the enmi- p er ty o f emulsionizing fats which the pancreatic juice 

 depend ? possesses in so extraordinary a degree, depended upon a 



ferment, which at the same time occasioned the remark- 

 able change to be immediately referred to, and which he termed the 

 'ferment emulsifJ In this view Bernard was wrong. It is apparently 

 only in an indirect way that a ferment leads to the emulsionizing 

 of the fats. 



Brucke has shewn that when an oil or a fat which contains a 

 mere trace of free acid is shaken with a weak solution of carbonate of 

 sodium an emulsion is readily obtained, whilst if the oil be perfectly 

 neutral no such emulsion is obtained. It will be shewn that at the 

 temperature of the body the pancreatic juice does lead to the acidifi- 

 cation of fats; as the juice moreover contains carbonate of sodium, the 

 conditions readily arise which are required for the production of an 

 emulsion. It is remarked by Kuhne, and with justice, that probably 

 the proteid matters in the pancreatic juice play an important part in 

 the emulsionising action 1 . 



Roberts states that he has been unable to obtain any extract of 

 pancreas which possessed any special power of emulsifying fats, but in 

 this respect he differs from other trustworthy observers who have 

 asserted that watery infusions of pancreas do possess such power, and 

 is unquestionably in error. 



The Pancreatic Juice decomposes the Neutral Fats. 



Bernard discovered that when emulsions are made by mixing 

 fresh, alkaline pancreatic juice with a neutral fat, such as olive oil 

 lard, and the emulsions are maintained at the temperature of the 

 animal body, an acid reaction is very soon developed. The obsei 

 vation has been confirmed again and again, by Berthelot amon^ 

 others. 



Claude Bernard had found that when butter is kept at the tem- 

 perature of the body with pancreatic juice, the odour of butyric acid is ; 

 soon perceived. 



Berthelot tried the experiment with synthetically prepared mono- 

 butyrin and, by the action of pancreatic juice upon it, obtained 

 besides undecomposed monobutyrin, a mixture of free glycerin, butyric \ 

 acid and a soap. 



According to ^he P ro perty which the pancreatic juice possesses 

 Bernard, pan- decomposing the neutral fats is shared by the pancreati< 

 creatic tissue tissue itself; it is indeed laid down by Claude Bern* 

 also decom- as ^ e characteristic of this tissue that it possesses the 

 property of instantaneously decomposing butyrin. 



1 Kuhne, Lehrbuch, p. 122. 



