16 GASTRIC DIGESTION OF PROTEINS 



stomach by the gastric juice, in which process there arise 

 a very small proportion of acid-albumin, a large quantity 

 of albumoses and a smaller quantity of more advanced diges- 

 tive products (peptone, peptoids, and perhaps some of the 

 crystallizable end-products). The portion which has been 

 dissolved passes for the most part into the small intestine, 

 where it rapidly undergoes further dissociation and resorp- 

 tion. A small residue is resorbed directly in the stomach; 

 the advanced products of digestion are next to be absorbed, 

 while albumoses are taken up with difficulty. " The author 

 has in a previous volume (Vol. I of this series, p. 77, et seq., 

 The Chemistry of the Tissues) taken occasion to indicate the 

 change of view which has arisen within the past decade in re- 

 spect to the albumoses, which in strict parlance are no longer 

 accepted. The schematic tables of the sequence of the 

 various types of ' ' albumoses ' ' and ' ' peptones ' ' in the course 

 of gastric digestion, on which so much time and labor used 

 to be expended, have today become practically meaningless. 

 But it is important, as established by Abderhalden and Lon- 

 don, that cleavage of aminoacids from the protein molecule 

 scarcely occurs at all in the stomach, as, too, that synthetic 

 polypeptids supplied are not appreciably affected. 42 The 

 velocity of solution depends upon the nature of the protein 

 (for instance, gelatine is " digested " much more rapidly 

 than serum-albumin or egg-albumin). The dissolved pro- 

 teins of the gastric contents correspond for the most part to 

 the old definition of ' ' albumoses. ' ' Another important mat- 

 ter is the rapidity of passage of the dissolved material in 

 the stomach into the intestine. It has been long known that 

 the degree of coagulation of the proteins is here an impor- 

 tant matter and that it makes decided difference whether 

 they are ingested raw or cooked. There are, moreover, 

 other items not well understood. For example, while raw 

 egg-albumin has left a dog's stomach, for the most part 



* E. Abderhalden and E. S. London, 1. c. 



