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DAIRY TECHNOLOGY 



the use of a perfectly tight cap, one that will withstand 

 the action of hot water and steam. Breweries have used 

 such a method of pasteurizing their bottled beer for a 

 number of years, while the dairy industry has but recently 

 adapted it to bottled milk. 



One of the objections to the commercially pasteurized 

 milk of to-day is that, although the pasteurization may 

 have been efficient, contamination during the cooling, 



FIG. 17. A type of beer-pasteurizing machine adaptable to the pasteuri- 

 zation of milk in bottles. (Circular 184, U. S. Dairy Division.) 



bottling and capping processes is inevitable, and this 

 contamination may be of a very serious nature. Pas- 

 teurization in the bottle prevents such contamination 

 and insures a safer product. 



Pasteurization of bottled milk is carried on to a limited 

 extent in steam sterilizers, but a more efficient process 

 is by the use of water. In the brewery there are two 

 general classes of these pasteurizers. In one type the 



