DAIRY HUSBANDRY 
53 
SERIES H 
TESTING BUTTER 
Materials necessary for 10 students: 
10—Yz pint glass top fruit jars (Ball Ideal). 
*10—Farrington Butter fat test bottles. 
10—Aluminum Beakers (125 cc.). 
10 — 4" spatulas. 
5—250 cc. volumetric flasks. 
1—Wisconsin high pressure oven, or 
5—Alcohol lamps, or 
5—Bunsen burners and Benkendorf ovens. 
25cc. —Potassium Chromate (K 2 CrOf) solution (F. & W. f 278). 
200cc.—Silver nitrate (. AgNoz) solution. (F. & W. If 278.) 
1 — Kg. petroleum ether or high test gasoline (for ether extrac¬ 
tion test). 
EXERCISE NO. 39 
Object: To become acquainted with the Farrington test for fat in butter. 
Procedure: The important step in testing butter as well as milk or cream 
is obtaining a correct sample. This is accomplished as follows 
when taken direct from the churn; bring butter up on table, 
wipe free moisture from above doors. Cut the top off butter 
with a ladle and with a spatula obtain a small sample (5-10 
grams each) from at least 5 different places along the full length 
of the butter, and place in the half pint glass top fruit jars. 
Seal the jar. Care should be exercised to avoid having free 
water dropping into the jar. 
If the sample is to be taken from a box, tub, or print, a trier 
should be used to obtain a representative sample. Do not 
shake trier to remove free w r ater. 
A. Warm the butter so that it is in a semi liquid condition, at a 
temperature of about 100° F. Beat with a spatula until it has 
a uniform, creamy consistency. Avoid oiling off. 
B. Weigh a clean, empty, especially constructed Farrington 
butter fat bottle, and record its weight. Pour into the bottle 
enough of the prepared sample to bring to about the 47 gram 
mark, weigh again, and by subtracting the first weight from 
the last, obtain the weight of the butter and record it. 
C. Place thebottle in a hot water bath (160°+F.) for fifteen minutes 
remove to a Babcock centrifuge and whirl at Lop speed in a hot 
tester for fifteen minutes. Place in a hot water bath at 140° 
F. for 10 minutes and read quickly the top and bottom of the 
fat column. Obtain the net weight of the fat by subtracting 
the smaller reading from the larger. 
