318 



JR. H. Chittenden — Papoid-digestion. 

 b. In alkaline solution, 2'0 per cent, sodium bicarbonate. 



Sodium chloride. Weight of undigested residue. Proteid digested. 



1-6233 grams 57-7 percent. 



1*0 per cent. 



1-6379 



56-6 ** 



2-0 



1-6779 



55-6 *' 



4-0 " 



1-7450 *' 



53-8 



c. In acid solution, 0-1 per cent, hydrochloric acid. 



Sodium chloride. 



Weight of undigested residue. 



Proteid digested. 







2-7o67 grams 



27-1 per cent. 



1*0 per cent. 



2-2862 " 



39-5 



2-0 '' 



2-2780 '* 



39-7 



4-0 " 



2-3344 " 



38-2 



d. In acid solution, 0'2 per cent, hydrochloric^ acid. 



The 10 grams cooked beef proteids contained 3*7767 grams of dry 

 proteid (110° C). 



Sodium chloride. 





Weight of undigested residue. Proteid digested. 











3-2872 grams 12-9 



per cent. 



1-0 per cent. 







31226 " 17-3 



(( 



2-0 " 







3-1138 " 17-5 



a 



4-0 " 







3-1023 " 17-9 

 Percentages of Proteid Big'ested. 



( ( 



Sodium chloride. Neutral solution. 



20 p. c. Bicarb, soda. 0-1 per cent. HCl 



. 0-2per cent. HCl. 



49-7 



per 



cent. 



57-7 per cent. 27-1 per cent. 



129 per cent. 



1-0 per cent. 52-1 







56-6 39 5 



17-3 



2-0 53-4 







55-6 39-7 



17-5 



4-0 52-7 







53-8 38-2 



17-9 



From these results, it is plain that sodium chloride or common salt 

 increases slightly the solvent action of papoid on coagulated pro- 

 teids in neutral solutions ; while in an acid solution, Q-l per cent, and 

 0*2 per cent, hydrochloric acid, it increases very greatlj'' the solvent 

 power of the ferment. This action of the salt we shall see later is 

 connected with a certain solvent power on one or more of the pro- 

 ducts of digestion, especially formed in acid solutions of papoid. 

 Salt by itself, or in connection with dilute acid, has practically no 

 power of dissolving the proteids of coagulated beef. In fact, the 

 presence of salt diminishes decidedly the ordinary solvent action 

 exerted by dilute acid alone. Thus, 0*2 per cent, hydrochloric acid 

 by itself, at 45° C, will dissolve about 4-6 per cent, of proteid mat- 

 ter from the 10 grams of coagulated beef in 5^ hours ; while in the 

 presence of 2-0 per cent, of sodium chloride, acid of the same 

 strength, under like conditions, \\\\\ dissolve only 2*6 per cent, of 

 the proteid. The salt counteracts the swelling action of the dilute 

 acid and thus diminishes its direct solvent power. 



