May s. 1923 
Fatty Acids in Butter Fat 
367 
As decomposition vitiates certain determinations in the analysis of 
oils and fats, the results fail to create a perfect entity, but with expe¬ 
rienced workers such errors may gradually be reduced to a minimum. 
2. FROM THE MILK OF SINGI.K ANIMAI^S, GRAD^ HOI^Tl^INS AND GRAD^ 
JHRSBYS, COMPARATlV^I,Y FR^SH IN LACTATION, F^D NORMAL RATIONS 
The cows in this test were fair types of their respective breeds and 
comparable in age. Cecile II had freshened more recently than the 
others. The Holsteins were a high-fat strain of moderate milk yield. 
The milk produced was the daily average for the period in which cream 
was saved for churning. The milk analyzed was a five-days’ composite, 
taken about the same time as the cream samples. The feeds, both grain 
and roughage, were average products of their kind of which analyses 
were not considered necessary. The results of this test are given in 
Table III. 
Table III.— Records of cows and milk analysis 
Colantha II. 
Samantha II. 
Cecile II. 
Peggy. 
Breed. 
Grade Holstein.... 
Grade Holstein.... 
Grade Jersey. 
Grade Jersey. 
Date of birth. 
Oct. 14,1914. 
Aug. 18,1909. 
Dec. x8y X912. 
.... 19x0. 
L^t calf dropped. 
July 3,1917. 
Aug. 16,1917. 
Oct. 10. IQX7. 
Aug. 9,1917. 
Condition on calving 
Good flesh. 
Good flesh........ 
(Jood flesh. 
Good flesh. 
Date served.. 
Oct. 22,1917. 
Oct. 26,1917. 
Nov. 24i 19x7. 
Nov. 8. 1917. 
Weight of ftniniftl.. 
r,ooo pounds.. 
1,19a pounds'. 
700 pounds (?)_ 
780 pounds. 
Daily ration: 
Hay. . 
18 pounds. 
24 pounds. 
7 pounds. 
17 pounds. 
Alfalfa. 
4. s pounds. 
Com stover. 
16... 
Gluten fe^. 
4 pounds. 
4. s pounds........ 
3.8 pounds. 
'3 pounds. 
Wheat bran. 
2.5 pounds. 
Ground oats. 
2 pounds. 
2. s pounds. 
X pound. 
Cora bran. . 
4 pounds... 
4 pounds. 
4 pounds. 
Milk produced (daily 
Oct. 22 to 25, 1917, 
Oct. 26 to 29,1917, 
Nov. 5 to 8, 19x7, 
Oct. x8t0 2i, 1917, 
average).^ 
23.7 poimds. 
29.7 poimds. 
24.3 pounds. 
17.6 pounds 
Milk analysis: 
Solick (gravimetric).... 
13.38 per cent. 
12.9s cent. 
14.43 per cent. 
15.82 per cent. 
Fat (Babcock).. 
4.40 per cent. 
4. ss per cent.. 
5.40 per cent. 
6.60 per cent. 
Proteids (N X 6.25)-... 
3.37 per cent. 
3.22 per cent. 
3.40 per cent. 
3.98 per cent. 
Lactose (by difference). 
4.87 per cent. 
4.47 per cent. 
4.92 per cent. 
4.45 per cent. 
Adi... 
. 74 per cent. 
. 71 per cent. 
. 71 per cent. 
. 79 per cent. 
* For the days cream was saved for churning. 
ANALYSIS OF BUTTER FAT 
The methods employed for the ordinary analysis of butter fat have 
been described previously ( 8 ). The use of glycerol potash for the deter¬ 
mination of insoluble acids and the preparation of stock has been super¬ 
seded, however, by alcoholic potash as less drastic in its action on the 
unsatmated acids; but even the latter under careful manipulation tends 
to induce intramolecular changes resulting in a loss of iodin absorption 
and to some extent an increase in alkali-consuming power due to in¬ 
stability of the resulting molecule, particularly with linolic, linolenic, 
and other highly unsaturated acids, as shown by Fittig, Varrentrapp, 
and Schrauth, summarized in another article (10, p, 362). Recent 
experiments, although incomplete, indicate that under control condi¬ 
tions such decomposition can be largely prevented with normal butter 
fat. The determination of stearic acid by crystallization from alcohol 
is unquestionably simple in theory but rather difiicult in practice except 
in a cold, dry atmosphere, since condensed moisture is a vitiating factor. 
The analysis of butter fat is given in Table IV. 
