29 



125- Iti another tube with a little olive oil add some bile, 

 shake and place in water-bath at 40° C. and compare the 

 emulsive effect with 124. 



126. Action on Fat. For this experiment it is necessary 

 that the fat (olive or almond oil) should be perfectly neutral. 

 ■Commercial oils usually contain free fatty acids. The fol- 

 lowing method has been recommended for neutralization by 

 Krukenberg. 



Place the oil in a porcelain capsule and mix it with not too 

 ■much baryta solution, (Baryta mixture is prepared by mix- 

 ing one volume of a solution of barium nitrate and two 

 volumes of barium hydrate, both saturated in the cold), 

 and boil for sometime. Allow it to cool. The unsapouified 

 oil is extracted with ether. The ethereal extract is separated 

 from the insoluble portion and the ether evaporated over 

 warm water. (The flame must not be brought near the ether. 

 I,et the water come to a boil, put out the flame and then put 

 the dish containing the ether upon the hot water). The oil 

 should now be neutralized. 



127. Take two test-tubes and fill each one-third full of 

 neutral oil. Add some blue litmus to color. In the first 

 tube place a small piece of fresh pig pancreas. Put both 

 tubes in the incubator from J4 to i hour or longer. Note 

 if any change of color occurs in the one with the pancreas, 

 due to the formation of fatty acids. 



128. Another form of the experiment is to mix the oil 

 with finely divided perfectly fresh pancreas in a mortar, and 

 keep it for a time at 40° C. It soon becomes acid, owing to 

 the formation of fatty acids. Test with litmus paper. 

 These experiments often fail and the existence of a fat split- 

 ting ferment is totally denied by .some. 



129. Action on milk. Dilute 2 cc. of cow's milk with 

 10 cc. of distilled water in a test-tube and add 5-6 drops of 

 pancreatic extract. Keep at 40° C. from )^ to i hour. 

 Note any change that has occurred. 



