May 5,1923 
Fatty Acids in Butter Fat 
369 
# 
A second extraction of the alcoholic residue and combined washings 
with ether is no longer considered necessary. A “high’^ side tube dis¬ 
tillation flask is employed in both the preliminary distillation of the esters 
and the fractionation. The number of fractions has been increased to 7. 
Fraction i, ranging to about 100'^ C.®, is the most volatile portion derived 
from the esters, largely ether but containing considerable ethyl butyrate. 
It is made to a volume of 500 cc. with ether and the alkali-consuming 
power of an aliquot is determined; from this the grams of ethyl butyrate 
can be calculated. Fractions 2 to 6 are now largely determined by 
weight, a small Troemner scale with prepared counterpoise being used, 
since the temperature uncorrected and influenced by the speed of distilla¬ 
tion has not proved entirely a safe guide. The content of ethyl oleate is 
no longer considered a prominent factor. By using an adapter on the 
end of the condenser little difficulty is encountered in changing flasks. 
The recovery in fractions 2 to 7 has been greatly increased and now 
averages 185 gm. from 300 gm. of butter fat, with a maximum of 216 gm. 
thus far. 
TablK V .—Weight and analysis of fractions (ethyl esters) 
C01.ANTHA II 
Fraction No. 
Range of 
fraction. 
Weight of 
fraction. 
Saponification 
number. 
lodin number. 
Ethyl oleate. 
•c. 
db 70 to 90 
90 to 165 
16510217 
217 to 257 
257 to 286 
28610317 
31710332 
Gm. 
Mgm. 
® 1 . 453 *197 
396,205 
337*924 
267.689 
238.602 
218.942 
200.959 
Per cent. 
3. 
5 . 
6 . 
7. 
Total. 
5-6093 
3-9590 
6.4436 
13-7516 
57-4804 
97.4166 
184.6605 
3-776 
7.241 
11.872 
14.216 
16.275 
22.324 
4.618 
8.854 
14.518 
17-384 
19.902 
27.299 
SAMANTHA II 
± 70 to 90 
90 to 166 
166 to 218 
21810258 
258 to 286 
28610317 
31710327 
“1,655.186 
385.988 
335-668 
270.757 
238.847 
217.020 
200.880 
3 . 
4 . 
5 . 
6 . 
7. 
Total. 
5-5964 
3.9766 
5-4594 
14-2372 
53-7426 
79-3705 
162.3827 
5-055 
8.944 
12.834 
14-605 
16.714 
19-797 
6.182 
10*937 
15.694 
17.860 
20.439 
24.209 
CKCII.^ II 
I. 
±70 to 100 
100 to 170 
17010220 
22010261 
261 to 286 
28610318 
31810326 
«2,084.412 
405*373 
357*188 
287.805 
249.297 
218.974 
204.804 
3 .. 
4 ... 
6. 
7.. 
Total. 
5-6765 
4.0712 
4.6266 
8.5821 
55*7372 
71.7496 
150.4432 
2.048 
3-725 
7-613 
10.207 
14.914 
19.707 
2.504 
4*555 
9*309 
12.481 
18.238 
24.098 
» Total alkali-constiming power of the fraction. 
• With a minimum of loo® C. the complete elimination of ether and alcohol is more definitely assured; 
otherwise these might vitiate fraction 2. 
