HEATING MILK PRFAIOUS 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. 



FIG. 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 



