Sept. 21, 1914 
Composition of Roquefort-Cheese Fat 
433 
diluting the ammoniacal solution with water as long as a precipitate 
separated, and fraction 7 by evaporating the entire filtrate from 6, 
acidifying with sulphuric acid, and extracting with ether. The 90.29 
grams of fat yielded 80.8707 grams of insoluble acids, of which 73.5933 
were recovered in the seven fractions. 
In this process of fractionation the disturbing factor is oleic add, 
which not only contaminates every fraction, but also further compli¬ 
cates the problem by giving rise to considerable quantities of dioxy- 
stearic add during the manipulation. From the quantity of oleic add 
recovered, which was calculated from the iodin absorption numbers of 
the several fractions, it was estimated that 23 per cent of the oldc acid 
was converted to dioxystearic add. There is a possibility that other 
unsaturated adds, more readily oxidized than oldc add, were present, 
but this problem has not been investigated. 
With the foregoing assumptions the composition of the seven fractions 
was calculated. The results are shown in Table VII. 
Tabi.Iv VII.— Weight in grams of the insoluble acids recovered by fractionating 80.8707 
grams of insoluble acids of Roquefort-cheese fat 
Add. 
Fraction No. 
Total 
quantity 
of add. 
1 
2 
3 
4 
5 
6 
7 
Oleic. 
Dioxystearic. . . 
Stearic. 
4- 6893 
1. 2101 
1. 7278 
17. 9023 
2. 2424 
• 5786 
5 - 9 22 3 
1. 5281 
O. 9262 
.2390 
!• 3358 
•3447 
IO. 7260 
2. 7676 
i-1558 
. 2982 
2 6. 9978 
6. 9663 
1. 7278 
25. 7609 
10. 2638 
. 7229 
*533 
Palmitic. 
3 * 2793 
2. 0347 
4.4381 
5.1170 
. 1412 
I. 4832 
Myristic. 
I. 6289 
.0527 
Lauric. 
. 6702 
.2265 
Capric. 
• 9 2 73 
Total. 
2 5 - 5 2 95 
8.1350 
17 . 0055 
2. 7896 
3-3621 
14 - 3903 
2- 3813 
73 - 5933 
If a correction be made for the oxygen absorbed, the acids not recovered 
amounted to 7.4045 grams. This loss would obviously consist chiefly of 
oldc, lauric, and capric adds. The amount of oldc add was known 
from the iodin number of the fat, and the capric add was assumed to be 
3.80 per cent of the original fat. The lauric acid could therefore be 
obtained by difference. The final results, together with the results 
given by Browne for cow’s butter, are summarized in Table VIII. 
Table VIII.— Percentage of acids in the fats of Roquefort cheese and cow’s milk 
Add. 
Roquefort 
cheese. 
Cow's milk 
(Browne). 
Add. 
Roquefort 
cheese. 
Cow’s milk 
(Browne). 
Butyric. 
Caproic. 
Caprylic. 
Capric. 
Lauric. 
Per cent. 
3 - 48 
4 - 73 
.58 
3. 80 
5 * 84 
Per cent. 
5 - 45 
2. 09 
•49 
•32 
2. 57 
Myristic. 
Palmitic. 
Stearic. 
Oleic. 
Dioxystearic. 
Per cent. 
II. 36 
28. 53 
1. 91 
38. 10 
Per cent. 
9.89 
38.61 
1.83 
32- 5 ° 
I. OO 
