392 
Journal of Agricultural Research 
Vol. XXIV. No. s 
The question naturally arises with butter fats Bg, and B^o, from 
cows receiving peanut, com, and soybean oils, as to whether the high 
iodin numbers might not be due in part to the direct assimilation and 
transference of linolic and linolenic acids from the oils fed to the butter 
fat. A number of determinations were made by the lead-salt-ether 
method with a view of obtaining some definite information on the sub¬ 
ject, of which those in Table XXX are fairly typical. 
TablB XXX. — Lead - salUether-soluble fatty acids 
Fatty adds 
Iodin 
Neutralization 
recovered. 
number. 
number. 
Per cent . 
Mgm . 
41. 86 
83.11 
217.94 
42. 55 
83.03 
218. 27 
Lead-salt-ether-soluble fatty acids recovered from butter fat are 
rarely pure liquid acids but are more or less contaminated with small 
quantities of water-soluble acids extremely difiicult to remove by wash¬ 
ing and of insoluble saturated acids that pass the filter. The results 
indicate, however, that with due allowance the liquid acids could not 
have contained any appreciable quantity of higher unsaturated acids 
than oleic. ^ 
II. SUMMARY OF DATA FROM MASSACHUSETTS AND ELSEWHERE, 
TOGETHER WITH SUCH GENERAL DEDUCTIONS AS SEEM WAR¬ 
RANTED 
Table XXXI. —Analysis of eg samples of butter fat from Massachusetts cows fed normal 
rations 
Saponification number (j).^mgm.). 
Acid number (a).(mgm.). 
Ether number (e).(mgm.). 
Iodin number. 
Equivalent in oleic acid.. .(per cent). 
Total fatty acids ( T ) (1.00--0.00022594 e ) 
Neutralization number (n) s/T .(mgm.). 
Free fatty acids { A ) ajn .(per cent). 
Soluble fatty acids ( s ) ( T — I ) .(per cent). 
Neutralization number.. (mgm.). 
Insoluble fatty acids (/) by alcoholic potash 
Neutralization number..^.(mgm.) 
Stearic acid by crystallization... .(per cent) 
Glycerol (0.00054703 e ) .(per cent) 
Refractive index^ (Abbe) 40® C. 
Colorimeter (Lovibond)' >^-inch cell. 
Average. 
Range. 
231.403 
224.626 
to 335.333 
2.049 
.927 
to 
3*657 
229.355 
222.186 
to 232.530 
28.461 
22.720 
to 
36.241 
31.315 
25*273 
to 
40.313 
94.818 
94.746 
to 
94.980 
244.051 
236.498 
to i 
248.383 
.840 
•383 
to 
1.502 
7.297 
6.470 
to 
8.601 
504.787 
460.664 
to , 
539*370 
87.519 
86.145 
to 
88.471 
222.362 
215.676 
to ; 
226.310 
15.on 
5*544 
to 
23.304 
12.546 
12.154 
to 
12.720 
1.4536 
1*4534 
^to 
1.4536 
Yellow 3.2 
Yellow 2 
.0 to 5.8 
Orange 1.4 
Orange i 
.0 to 1.8 
1 Twelve samples. 
