THE PASTEURIZATION OF MILK 



sold at the popular price. It can, however, be 

 used on bottles containing milk sold at advanced 

 prices, like Certified Milk, Grade A, etc. The 

 second objection is that since the milk expands 

 upon being heated, the bottles cannot be entirely 

 filled. The bottles must therefore be made of a 

 size especially large, and customers must be 

 taught that bottles which are not full do still in 

 fact contain the full measure of milk. A third 

 objection advanced has been that milk in bottles 

 which are not full is more likely to become shaken 

 up, and the cream disturbed, than is the case in 

 bottles completely filled. This objection is 

 probably not of serious moment. A fourth and 

 rather serious objection is that the expense in the 

 consumption of heat units is much greater than 

 when other methods of pasteurizing are employed. 

 The reason for this is that the mass of glass in 

 the bottle nearly equals the mass of the milk, and 

 that since both bottle and milk must be heated 

 and also cooled, nearly double the amount of heat 

 is necessary, and a proportionately great amount 

 of cooling medium is used. In large plants this 

 added expense is very considerable. 



An attempt has been made to overcome this last 

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