BULLETIN 1344, U. S. DEPARTMENT OF AGRICULTURE 
some previous process to which the milk had been subjected. Al- 
though in a majority of cases there was a decrease in cream volume 
as a result of pasteurizing at 145° F., the decrease was not usually 
great enough to be readily noted on a bottle of milk by consumers. 
Table 1. — Effect of temperature of pasteurization on ordinary market milk 
Original raw 
milk 
Raw control 
after clarifying 
or pumping 
Milk pasteurized at— 
Test No. 
143 c 
F. 
145 c 
F. 
147° to 148° F. 
Cream 
volume 1 
Butter- 
fat in 
under 
layer 
Cream 
volume 
Butter- 
fat in 
under 
layer 
Cream 
volume 
Butter- 
fat in 
under 
layer 
Cream 
volume 
Butter- 
fat in 
under 
layer 
Cream 
volume 
Butter- 
fat in 
under 
layer 
1 
( 2 ) 
( 2 ) 
( 2 ) 
( 2 ) 
14.0 
14.0 
13.5 
9.0 
16.0 
12.5 
13.5 
14.75 
7.0 
13.5 
13.5 
16.0 
16.0 
13.5 
12.0 
13.0 
17.0 
17.0 
14.75 
16.0 
15.0 
15.0 
13.0 
15.0 
14.0 
14.0 
15.0 
15.0 
13.0 
14.0 
14.0 
13.0 
14.0 
13.5 
Per cent 
~~~6.~80~ 
.7 
1.2 
1.7 
.3 
1.0 
1.0 
1.0 
2.2 
1.1 
1.1 
.85 
1.5 
1.2 
11.5 
20.5 
20.5 
19.0 
13.0 
13.0 
11.0 
9.0 
15.0 
11.5 
11.0 
13.5 
6.0 
12.5 
12.5 
14.0 
16.0 
13.5 
11.5 
12.0 
17.0 
17.0 
14.0 
16.0 
15.0 
15.0 
14.0 
15.0 
14.0 
14.0 
15.0 
15.0 
13.0 
13.0 
14.0 
12.0 
13.5 
13.5 
Per cent 
1.1 
1.1 
1.3 
.90 
.80 
.80 
1.6 
1.7 
.4 
1.3 
12.0 
19.5 
17.5 
17.0 
13.0 
12.0 
Per cent 
0.75 
.70 
.90 
.80 
.90 
.95 
11.0 
16.0 
14.0 
14.0 
Per cent 
0.9 
"~L35~ 
.90 
8.5 
11.5 
9.5 
9.5 
Per cent 
1. 50 
2 . 
1.40 
3 
2.45 
4 
1.65 
5 
6 
7 
12.0 
11.0 
.90 
1.20 
8 
" 9." 6" 
9 . 
15.5 
.3 
1.2 
10 
18.5 
10.5 
13.0 
9.5 
12.0 
11.0 
12.0 
16.0 
11.5 
10.5 
9.0 
1.65 
1.40 
1.0 
1.3 
1.3 
1.4 
.9 
.8 
1.5 
11 
12 
1.1 
2.4 
1.3 
1.3 
1.10 
1.5 
1.2 
"-~i.~6"" 
10.0 
13 
14 
12.5 
1.25 
15. 
16. 
10.0 
1.67 
17 
18 
12.5 
13.0 
12.0 
.7 
."9 _ " 
11.0 
1.6 
19. 
20. 
1.85 
7.0 
11.5 
2.15 
21 
22. 
16.0 
13.0 
15.0 
13.5 
13.0 
11. 5 
23. 
24 
25 
,__. 
26 
27 
28. . 
13.5 1 
13.0 
12.0 
12.0 
12.5 
12.5 
29 
30 
31. 
32 
13.5 
14.0 
33 
11.5 
11.5 
9.0 
11.0 
11.0 
11.0 
34 
35.. 
36 
I I... 
37 
38. 
I I 
1 Cream volume is the number of cubic, centimeters of cream rising to the top of 100 cubic centimeters of 
milk left standing for 20 to 24 hours in a straight-sided graduated cylinder. (See page 3.) 
3 Samples 1 to 4, inclusive, were pasteurized in the laboratory, and samples 28 to 33, inclusive, were pas- 
teurized at the dairy hall of the division of dairy husbandry, University of Minnesota. All others were 
taken at commercial pasteurizing plants. 
EFFECT OF HEATING MILK TO VARIOUS TEMPERATURES 
In Table 2 are shown the results of heating milk to temperatures 
varying from 138° to 148° F. All these samples were taken before 
the milk was subjected to the 30-minute holding period. 
The control samples upon which the percentages of difference 
in this table are computed were from the raw milk entering the 
heater; and in the case of vat pasteurizers, just before the heating 
medium was turned on. In some instances the milk had been clari- 
fied or pumped, or both, depending upon the routine procedure 
carried out at the plant where it was collected. 
