694 
Journal of Agricultural Research 
Vol. V. No. is 
were all made in 0.5 per cent sodium carbonate. Although trypsin 1 and trypsin 3 
had the same total nitrogen contents (see Table VII), trypsin 1 was the more active 
preparation. This is evident from the fact that in experiments 18, 20, and 22 (Table 
X) digestion had proceeded as far in seven hours as in experiments 32 and 34 at the 
end of six hours, although in the latter experiments twice the weight of trypsin was 
used. 
The 100 c. c. portions of digestion fluid were neutralized with 24.5 c. c. of 2 AT 2/5 
sulphuric acid, the exact strength of which was N 2/5 X 0.98. This was sufficient to 
neutralize the sodium carbonate present and leave about 0.5 c. c. of the acid in excess, 
preventing the escape of ammonia when the mixture was brought to a boil. The 
filtration and determination of total nitrogen in the precipitated alkali proteinate 
and in the filtrate were carried out as described in the acid digestions. 
It is to be noted that, while small amounts of pepsin in hydrochloric acid will 
rapidly digest meat proteins to the proteose and peptone stage but no further, trypsin, 
although much slower in its action, will further split the meat proteins into amino 
acids. This is the reason for the data under “Quantity of Nj$ proteose, peptone, 
and amino-acid nitrogen” in Tables X and XI. The statement of results in Table X 
is, in general, similar to that in Table IX. 
The conditions of experiments 15 to 24 were as follows: In each experiment the 
digestion mixture consisted of 100 gm. of meat plus 2,000 c. c. of 0.5 per cent sodium- 
carbonate solution plus 2.000 gm. of trypsin 1; except experiment 15, in which 2,000 
gm. of pancreatin 1 was used. For nitrogen determinations, 100 c. c. of digestion 
fluid, equivalent to approximately 5 gm. of meat, were used. 
Table X .—Rate of formation of proteoses, peptones , and amino acids in trypsin-sodium- 
carbonate solution 
QUANTITY (IN CUBIC CENTIMETERS) OP N/s PROTEOSE, PEPTONE. AND AMINO-ACID NITROGEN 
Experiment No. 
Digestion period. 
is 
16 
18 
20 
22 
'24 
Beef 
sam¬ 
ple 4. 
Veal 
sam¬ 
ple 4. 
Beef 
sam¬ 
ple 4. 
Veal 
sam¬ 
ple 4. 
Beef 
sam¬ 
ple 5. 
Veal 
sam¬ 
ples- 
Beef 
sam¬ 
ple 6. 
Veal 
sam¬ 
pled. 
Beef 
sam¬ 
pled. 
Veal 
sam¬ 
pled. 
Beef 
sam¬ 
ple 7. 
Veal 
sam¬ 
ple 7. 
Hours. 
5 - 0 
6* s 
9*3 
7 * 7 
n. 4 
9*3 
9.2 
8.4 
7 * 7 
6.2 
7*8 
13*8 
20.3 
8.1 
4 . 
10. 7 
16. 5 
11. 7 
17.9 
16.9 
“28.3 
15*4 
“28.1 
20. 7 
29.8 
16.6 
25.6 
18.5 
29.1 
16.0 
24.6 
14*5 
23.0 
13*4 
21.1 
14.0 
19* 2 
7 . 
22. 2 
23 -S 
a 34 * 1 
° 34 - 7 
38* 7 
33*3 
37-4 
3 i *5 
30.2 
2d. 2 
2d. 1 
22.9 
33 * 7 
34 * 1 
42.9 
43*6 
47*6 
42. 2 
46. 7 
40.6 
43 - 7 
36.8 
36*9 
28.5 
Theoretical maximum 
52 - 7 
46.1 
53*2 
46. 6 
53*4 
48*3 
54 * 1 1 
44.1 
54*1 
44.1 
5 °* 1 
32*5 
Extractive nitrogen.. 
7.2 
8.4 
7.2 
8.4 
7.2 
7*8 
8.1 
7*7 
8.1 
7*7 
11.9 
2d. 2 
Trypsin nitrogen. 
4.1 
4*1 
4*3 
4*3 
4*3 
4*3 
4*3 
4*3 
4*3 
4*3 
4*3 
4*3 
QUANTITY (IN CUBIC CENTIMETERS) OP N/s ALKALI-PROTEINATE NITROGEN 
I. 
3. 7 
2.9 
3. 7 
2. 0 
3.3 
2.9 
4.0 
2. d 
3 * 0 
2. 3 
3.1 
3. Q 
d.8 
4. 2 
d.8 
5.3 
4. 2 
4.4 
4.8 
4. 0 
4. 0 
d. 5 
4. 7 
3, O 
7.6 
5.1 
a d. 2 
0 5 * 3 
4. 2 
5 * 7 
5* 0 
S* o 
4.3 
9.8 
5. 0 
3. 3 
7. 
8. d 
6.9 
a S* 7 
08.2 
4. 4 
7. 6 
5. 5 
5*8 
4.8 
10.6 
4 * 9 
2 .0 
*4 . 
6.9 
8*3 
3-3 
4*2 
4*3 
4*9 
3*1 
S*r 
3 *o 
6- 7 
3*6 
1.6 
Trypsin nitrogen. 
0. d 
0. d 
0. d 
0. d 
0. d 
o.d 
0. 6 
0. d 
o.d 
0. d 
Age of meat, days.... 
1 
1 
9 
9 
7 
7 
2 
2 
21 
21 
33 
33 
a Results are for five and eight instead of four and seven hours. 
