DIGESTION AND An SORPTION OF FA TS. 443 
Minkowski and Abelmann 1 found, after complete removal of the 
gland in dogs, tbat <>n an average 44 per cent, of proteid was absorbed : 
after partial removal, 54 percent. The amount of absorption was much 
increased on giving raw pancreas with the food. Sandmeyer 2 obtained 
similar results. ( >n removal of all but one-fifth to one-fourth of the gland 
(the portion remaining behind not being in communication with the 
intestine), 60 to 70 per cent. of proteid was still absorbed, and, on adding 
a supply of finely-minced pancreas to the food, the absorption of proteid 
became almost normal. 
DIGESTION AND ABSORPTION OF FATS. 
The pancreatic juice is the only digestive secretion which contains an 
enzyme possessing a chemical action ou the neutral fats. 3 This action 
consists in splitting the fats into fatty acids and glycerin, 4 and may 
be demonstrated in one of the following ways : — 
1. A neutral fat is first obtained, e.g., by thoroughly shaking olive 
oil with sodium carbonate solution and ether, pipetting off the ethereal 
layer, filtering if necessary, and finally allowing the ether to evaporate, 
when a neutral fat is left behind. This is mixed either with fresh 
pancreatic juice, or an extract of the fresh gland prepared as already 
described, and the mixture, after being coloured blue by the addition 
of litmus, is placed in a bath at 37° to 40° C. The alkaline reaction is 
seen gradually to change into an acid one. 
2. Instead of adding litmus, after the mixture of neutral oil and 
pancreatic juice, or extract, lias digested for some time (half to two hours), 
sodium carbonate solution is added (which converts the free fatty acids 
formed into soaps), and the unattacked fat is removed by repeated 
extraction with ether. The residue is next treated with dilute 
sulphuric acid, setting free again the fatty acids, which are extracted 
witb fresh ether, and recovered after its removal by evaporation. 
.'!. The formation of free fatty acid may be also qualitatively shown, 
by removing water from the fresh, finely-divided gland, with 90 per cent, 
alcohol, drying it with filter paper, and then covering it with a neutral 
ethereal solution of butter, obtained by shaking up milk or cream with 
ether and a solution of caustic soda. "When this material is kept for a 
short time at 37° to 40" C, a distinct odour of butyric acid appears ; and if 
the mixture has been previously rendered blue by litmus, this turns red. 
Form in which fats are absorbed from the intestine. — There has 
been much discussion as to the extent to which the decomposition 
of the fats by the pancreatic enzyme, as above described, takes place 
in the intestine ; and also as to the subsequent fate in the intestine 
of the fatty acids formed therein. According to the views held on 
1 " Ueber die Ausnutzung tier Xahrungsstoffe nach Pancreasextirpation," lining. Diss., 
Dorpat, 1890; Jahresb. u. d. Fortschr. d. Thier-Chem., Wiesbaden, 1890, Bd. xx. S. 45. 
fZtschr.f. Biol., Miinchen, 1895, Bd. xxxi. S. 35. 
3 Fats are said to undergo a certain amount of decomposition into fatty acids in the 
stomach (Marcet, Proc. Hoy. Soc. London, 1858, vol. ix. p. 306; Cash, Arch. f. Anat. u. 
Physiol., Leipzig, 1880, S. 323); the cause of this decomposition is unknown, but it is 
probably bacterial during the first stage of gastric digestion. 
4 Bernard, Compt. rend. Acad. d. sc, Paris, tome xxviii. ; Arch. gin. de mid., Paris, 
1849; "Memoire sur le pancreas," Paris, 1856; " Lecons tie physiologic exp^rimentale," 
tome ii. p. 256. For the chemical ecpiations representing such a decomposition, see 
Chemistry of the Fats, p. 19. 
