UNSWEETENED CONDENSED Mink Dr¥rcrs 261 
evaporated nulk, owing to the process of manufacture and the 
condition of the product, is destined to separate its fat, the turn- 
ing of the cases, while at the factory, cannot permanently prevent 
separation. \Where the goods are consumed immediately after 
they leave the factory, this practice may serve the purpose; but, 
since the large bulk of evaporated milk manufactured, is exposed 
to prolonged storage, its advantage is very limited. 
Effect of Homogenizing —Under average conditions careful 
attention to the precautions above discussed will greatly mini- 
mize and often prevent fat separation. \t best, however, much 
of the evaporated milk on the market shows signs of separation 
after sixty to ninety days and some of it even after two weeks, 
for the fundamental cause of separation, the difference in gravity 
between the fat globules and the rest of the milk constituents, 
is still present; then again, under less favorable conditions, even 
the above precautions may not prove adequate to Keep the fat 
from separating. 
‘Phe introduction of any agent or process, therefore, capable 
of permanently removing this fundamental cause, must prove 
a lasting benefit to the manufacturer of evaporated milk. This 
agent has been found in the homogenizer. ‘The homogenizer 
makes it possible to divide the fat globules so finely, that their 
buoyancy or gravity force is not great enough to overcome the 
resistance of the surrounding liquid. They are unable to rise to 
the surface, but remain in homogeneous emulsion, 
It is quite probable that aside from the reduction of the size 
of the fat globules, the efficiency of the homogenizer to prevent, 
fat separation is due also to the physical change of the casein as 
the result of homogenization. ‘The casein becomes more viscous. 
The chief objection to the use of the homogenizer is its 
effect on the casein of the milk, when subjected to excessive pres- 
sure. Beyond certain limits of pressure homogenization so 
affects the casein, that the latter is mere prone to curdle in the 
sterilizer. Powever, experience has amply shown that the maxi- 
mum pressure required to prevent fat separation in the finished 
product, is not great enough to seriously affect the behavior of 
the casein during sterilization. Hence, the proper regulation of 
