CREAMERY PROBLEMS. 43 
the readings obtained is illustrated in the following table. Ten 
samples of cream were tested in duplicate, and the readings 
made at a temperature of 130° with the average result of 20.94 
per cent. Ata temperature of 180° F. the readings were 21.36 
Pe ecent:, Or, 42, per cents higher. 
ABLE or: 
Comparative Readings of Cream Tests at different Temperatures. 






bth cae | on 
es state | Os 
we S we % | $s 
No. OF SAMPLE. ma OM mom Hat 
Sos eos | ee 
ye O veo opener 
mv mv Dogme 
al 
ae - 2 a | 
% N | O7, 
NO oT. = “ 3 4 - 22.80 23.25 | .45 
ai 
IN Gace 2, ee - . - - 18.80 19.25 .45 
ING 3. - .7 - - - - E00 jy oy | 634 
INR t oe A - - - - - : 19.08 19.50 .42 
No. 5. - . - - - - 15.00 15.25 | oo 
"Tt 
ios. 0}, - - - - - - 26.70 2752, 55 
7, - - - . - - 26.50 27.00 | .50 
ING. 8, - - - - - : 23.00 23.50 | .50 
VO eO.-. © - - - - - - 22625 B2UTE | .50 
No. 10, - - - - - - Lae 18.50 pas 
Average, - - - - = - 20.94 2130 .42 




The coefficient of expansion for butter fat is .000355 for each 
degree F. (122° to 212°). The amount of fat representing 5 
per cent. occupies a volume of rcc. The theoretical difference 
in the volume of fat at two temperatures may be calculated as 
follows: coefficient of expansion < cc. of fat « difference of 
degrees of temperature. In the case of 21 per cent. cream the 
volume of fat at 190° would be .07455 cc. (.000355 X 245 X 50) 
greater than at 140°. Since 1 cc. of fat represents 5 per cent., 
the reading at 190° would be .07455 X 5==.37275 per cent. too 
high. ; 
ERROR IN MEASURING CREAM FOR BABCOCK TEST. 
The usual method of taking a sample of cream for the Bab- 
cock test is to measure out 18 cc. Cream may contain from 
12 to 60 per cent. of fat. The more fat cream contains, the 
less its specific gravity and the less a given volume will weigh. 
