98 THE PANCREATIC JUICE. 



latter has been set free by the ferment, nor will it emulsify 

 the fat if there is no fatty acid present, but a fine emulsion 

 is produced after the decomposition, and the rest of the 

 fat becomes thereby capable of being absorbed through the 

 walls of the intestine. 



The decomposition of the fat-molecule is as follows: 



C 3 H 6 (C 18 H 36 2 ) S + 3H 2 = 80 1T H,.00,H + C 3 H 5 (OH) 3 . 



stearin stearic acid glycerin 



The fat-splitting ferment is easily destroyed by acids; 

 hence it may not be found in a gland which has been kept 

 until it has an acid reaction. 



211. Make a watery infusion of the pancreatic gland, 

 as in the trypsin digestion. If it is not already neutral 

 make it so. Add to it in a test-tube a few drops of some 

 neutral fat, like olive-oil, and let it stand for half an hour 

 in a beaker of water at about 38, shaking occasionally to 

 keep the two liquids well mixed. Then test it with a piece 

 of blue litmus-paper. It will turn the paper red from the 

 fatty acid which has been set free. 



212. Mix 10 cubic centimeters of cream or rich, milk with a 

 little powdered blue litmus, shaking well until an even blue color 

 is obtained. Divide in two test tubes. To one add boiled pan- 

 creatic extract and keep at a temperature of 38; to the other 

 unboiled. The former remains blue, the latter becomes red from 

 the cleavage of the butter-fat into fatty acids and glycerin. 



213. Shake, in a test-tube of water, to which a few drops 

 of sodium carbonate have been added, a few drops of olive-oil 

 which does not contain free acids. (Since the oil easily becomes 

 decomposed on standing, it may be necessary to remove the free 

 acids by first shaking with very dilute sodium hydrate solution 

 and ether. Separate the ether from the water, wash well by 

 shaking it a number of times with pure water, and allow it to 

 evaporate at a gentle heat away from a fire or lamp. The alkali 

 has united with the free acid to form a soap, and this has been 



