12 
LABORATORY MANUAL 
cent of fat may be obtained by subtracting the reading ob¬ 
tained at the base of the fat column from the reading obtained 
at the top of fat column. 
Note: (1) Since sulfuric acid is very corrosive, great care 
should be exercised when handling it. 
(2) Acid bottles should be kept stoppered when not in use. 
(3) The enclosed type of testers are preferable and they should 
be kept closed when operated. 
Observations: Record results as follows: 
Sample 
% fat 
Color of 
fat 
Condition 
of fat 
Condition of 
acid mixture 
1 
2 
3 
Conclusion: 
Questions: (1) Describe how a sample of frozen milk should be obtained 
for the Babcock test. 
(2) Why are bottles filled twice with hot water and whirled three 
times rather than filling once and whirling once? 
(3) When should a water bath at 120°-140° F. be used when test¬ 
ing? Why? 
(4) Why is the acid poured in such a manner that it runs down the 
side of the bottle under the milk, and not directly into the 
milk? 
References: F. & W 7 . If 29-42, inclusive, 66; Van S. p 23, 57-70; Jud. pp. 
41-75; St. pp. 112-119. 
