June is, 1914 
Ripening of Cheddar Cheese 
199 
Table; V. — Substances formed by the action of Streptococcus b % 
[Computed in cubic centimeters of tenth-normal solution! 
Substance. 
Quantity found. 
Control. 
Quantity produced. 
Flask 1. 
Flask 2. 
Flask 1. 
Flask 2 . 
Total volatile acids. 
Formic acid. 
Acetic acid. 
Propionic acid.. 
Butyric acid. 
Caproic acid. 
Acids from alcohol. 
Formic acid. 
88. 799 
3 - 153 
68. 190 
10. 209 
2. 090 
5 - *57 
7 - 743 
• 3 i 3 
6. 908 
. 522 
4 - 739 
*443 
3 - 979 
* 3 i 7 
65. 982 
. 000 
9°. 474 
, OOO 
69. 150 
9. 970 
3. 821 
7 * 533 
5 -158 
. OOO 
4. 612 
. 546 
4.856 
. OOO 
4.651 
. 205 
47.090 
. OOO 
14- 530 
8. 295 
6- i 3 S 
. OOO 
. OOO 
. IOO 
•375 
74. 269 
-5. 142 
62. 055 
10.209 
2.090 
5 - °S 7 
7. 368 
• 3*3 
6 - 533 
. 522 
3* 906 
•443 
3. 146 
•317 
-18.818 
. OOO 
75-944 
- 8.295 
63 - 01 5 
9 - 97 ° 
3- 821 
7-433 
4- 783 
Acetic acid. 
Propionic acid. 
Acids from esters. 
Formic acid. 
Acetic acid. 
Propionic acid. 
Citric acid. 
Total lactic acid. 
Racemic lactic acid. 
•833 
84. 800 
. OOO 
• 546 
4.023 
. OOO 
3.818 
. 205 
-37.710 
. OOO 
Active lactic acid. 
Ammonia.grams. . 
•045 
.052 
.023 
. 022 
. 029 
The data in Table V show the same general indications as the data 
in Table IV. A larger increase was shown in total volatile acidity. 
Comparatively a much greater increase was noted in the case of butyric 
and caproic acids. A greater increase was also evident in alcohol and 
ester production, ethyl alcohol and acetic acid in ester combination pre¬ 
dominating. A minute quantity of formic acid previously existing in 
ester compounds and also from methyl alcohol was recovered. Since 
probably only about 6.2 per cent of esters are recovered in the method 
used, the amount of esters actually found indicates a preexisting quan¬ 
tity of those bodies equivalent to 64.8 c. c. N/10. This quantity is 
greater than the ester content of any cheese examined. If this organ¬ 
ism is an agent which produced esters in cheese, as the data indicate, 
it would, however, be subjected to inhibiting influences in the cheese 
mass and probably not be able to form esters in such great quantities as 
when in pure culture. 
The culture of Streptococcus (Table VI) was 2% months old when 
analyzed. The medium had a pleasant nutty odor and a slightly acid 
taste. A soft custard-like curd had formed; that in flask 2 showed the 
greater bacterial action, having a more acid odor, but the taste was simi¬ 
lar to that in flask 1. The curds were alike, with a clear supernatant 
liquid. The cheese from which this organism was isolated was 133 days 
old and contained the organism to the extent of 170,000,000 per gram. 
It had a mild Cheddar flavor after 4 months of curing. 
43841 0 —14—3 
