HEATING MILK PREVIOUS TO SKIMMING. 121 
as when heated after the skimming process has been com- 
pleted. 
(3) Less heating and cooling apparatus is necessary. 
(4) Closer skimming. 
How Heated.—There are two methods by which milk is 
heated previous to skimming. First, by the use of direct 
live steam; second, by the use of heaters which heat with 
steam or hot water indirectly. 
Fic. 68.—The Twentieth-century milk-heater. 
Heating of milk with direct live steam is accomplished in 
two ways: first, by entering a steam hose into the vat full 
of milk; and, second, by making use of special heaters, which 
allow steam to come in direct contact with the milk as the 
milk passes through. 
The method of heating milk with direct live steam cannot 
be too strongly condemned, because it leaves bad effects upon 
the flavor of the butter. At the Milwaukee National Butter 
contest in 1903, where over eight hundred exhibitors were 
represented, the authors noticed that where the criticism 
“burnt, oily flavor” was made on the score card, the milk 
from which the butter was made had in most cases been heated 
with live steam. The burnt flavor may possibly be due to the 
sudden excessive heat to which the milk will be exposed when 
coming in .contact with live steam. The greatest danger, 
however, in heating milk with live steam is, that impurities 
from the pipes and boiler are likely to be transmitted to the 
