MILK-PLANT OPERATION. 
45 
water and using the specific gravities of milk and cream of various 
percentages as given in United States Department of Agriculture 
Bulletin No. 98, the following table has been worked out as to the 
weights per gallon, at a temperature of 68° F. 
Table 15. — Weight per gallon and specific gravity of milk and cream having various 
fat contents. 
Commodity. 
Fat 
con- 
tent. 
Specific 
gravity. 
Weight 
per 
gallon. 
Commodity. 
Fat 
con- 
tent. 
Specific 
gravity. 
Weight 
per 
gallon. 
Per 
cent. 
1.000 
1.037 
1.034 
1.033 
1.032 
1.031 
1.030 
1.025 
1.018 
1.015 
Pounds. 
8. 32162 
8. 6295 
8.6045 
8. 5962 
8. 5879 
8. 5796 
8. 5713 
8. 5297 
8. 4714 
8.4464 
Cream 
Per 
cent. 
20 
22 
25 
28 
30 
32 
35 
38 
40 
1.013 
1.011 
1.008 
1.006 
1.004 
1.002 
.999 
.997 
.995 
Pounds. 
8. 4298 
0.025 
3 
3.5 
4 
5 
6 
10 
15 
18 
do 
8. 4132 
Milk 
do 
8. 3882 
Do .. 
do 
8. 3715 
Do 
do 
8.3549 
Do 
do.... 
8.3383 
Do ... 
do 
8. 3133 
do 
8.2967 
Do. .. . 
do 
8.2800 
Cream 
Weights are given at 68° F. because that is the temperature used 
in determining the specific gravities, being equivalent to 20° C, 
the temperature generally used for such work. There would be a 
slight difference for milk at 50° to 60° F., the temperature at which 
milk is usually received at the plant. 
The determinations above were made on standardized milk and 
cream, that is, mixtures of skim milk and cream of various per- 
centages of butterfat. Figures for normal milk containing from 3 
to 6 per cent butterfat would vary slightly from those given. For 
all practical purposes the weight of whole milk may be figured at 
8.6 pounds a gallon. 
