54 
LABORATORY MANUAL 
D. Calculate the per cent fat as follows: 
Net reading 
- X 100 = % fat. 
grams butter in bottle 
Note: A sharper dividing line may be obtained by dropping 
a small quantity of strong hot salt water through the fat after 
whirling. 
Obser\ations: 
Sample 
Weight of Butter 
Net Reading 
% fat 
1 
2 
Conclusions: 
Questions: (1) Name four other fat tests which may be used for de¬ 
termining the fat content of butter. 
(2) Why is the Babcok test not commonly used for determining 
the fat content of butter? 
(3) How is the silver nitrate solution for the salt test, described in 
exercise 41, prepared? 
(4) How is the indicator for the butter salt test prepared? 
References: F. & W. 102—103d, inclusive, 278, 278a; Van S. pp. 112— 
130; Jud. p. 86. 
