ON BUTTERMAKING 19 



2. Intermittent ; that is, heating and cooling milk 

 alternately several times with the idea of allow- 

 ing spore development between heatings. After the 

 third heating to a high temperature, practically all 

 bacteria and spores are destroyed. 



What is sterilization? 



This term is often wrongly used in place of pas- 

 teurization. To sterilize milk it must be heated to 

 very high temperature under pressure. Milk is not 

 sterile until every bacterium and spore is destroyed. 



What are the advantages of pasteurization in butter- 

 making? 



1. Most bacteria can be destroyed in milk and 

 cream. 



2. Commercial starters can be prepared and 

 carried on for indefinite periods. 



3. Pasteurization of skim milk prevents trans- 

 mission of tuberculosis and other such diseases 

 through its medium. 



4. Many volatile and food flavors can be re- 

 moved from milk and cream. 



5. Cream ripening can be more successfully con- 

 trolled. 



6. A more uniform quality of butter can be 

 made. 



7. Butter has better keeping quality. 



8. Enables separators to skim closer. 



What are the disadvantages of pasteurization in 



buttermaking? 

 I. Cost of machinery, fuel and labor. 



