2(. 



The American Public Healtii Association 



active co-operation of engineers and 

 laboratory investigators and that any 

 complete or satisfactory study of even 

 one plant calls for considerable effort. 

 The great importance of efficiency in 

 the ever increasing application of 

 pasteurization processes to market 

 milk and cream and other dairy prod- 

 ucts warrants a concentration of ef- 

 fort by both official and industrial 

 agencies upon this phase of milk and 

 dairy product supervision,, even, if 

 necessary, at the sacrifice of other in- 

 spectional or analytical investigations, 

 the results of which do not have such 

 a direct bearing upon the actual pre- 

 vention of the transmission of disease. 



VII. State and Municipal Supervision 

 of the Pasteurization of Milk. 



The Committee has carefully review- 

 ed those parts of the milk ordinances, 

 governing pasteurization, of practically 

 every city of over 2.t,000 inhabitants 

 in the United States, and does not feel 

 that any one of them affords the full 

 protection against ineffective pasteur- 

 izers and faulty operation that should 

 be assured for so important a process. 

 The legal authority controlling pasteur- 

 ization grades all the way from ordin- 

 ances that merely state that milk from 

 tubercular cows shall be pasteurized 

 and then do not define pasteurization, 

 to the more complete and carefully 

 thought out laws governing pasteuriza- 

 tion plants for NeAV York, Sr^n Francis- 

 co and Chicago. In the opinion of the 

 Committee, none of them are adequate 

 in light of careful studies of the various 

 types of pasteurizing apparatus and the 

 careless handling that frequently is 

 met. 



In reviewing many of the ordinances, 

 the Committee has been impressed with 

 the feeling that the framers of the re- 

 gulations look upon pasteurization as 

 merely a means for putting dirty milk 

 on the market, without too greatly 

 jeopardizing the health of the con- 



sumer. This is a great mistake, and 

 no ordinance should be so worded as 

 to permit a feeling to arise; in the 

 minds of the public that pasteurized 

 milk is necessarily inferior to raw milk ; 

 in fact, if any impression is to be given 

 by such regulations, it should be that 

 pasteurized milk is preferable to the 

 raw product. In the opinion of the 

 Committee, any ordinance to be com- 

 plete and effective must contain the 

 following points : A definition of 

 pasteurization ; a statement of the tem- 

 perature and time that shall be used ; 

 temperature to which milk shall be 

 cooled, etc ; the objects to be obtained, 

 namely ultimate bacterial count, etc; 

 regulations governing construction of 

 the apparatus and equipment; control, 

 namely, the organization to have super- 

 vision of the process; and finally, pen- 

 alties to be imposed for failure to com- 

 ply with the provision of the ordinance. 

 (1) Time and Temperature Require- 

 ments. The Committee feels that no 

 milk should be considered pasteurized 

 that has not been heated to a tempera- 

 ture not lower than 145 degrees F. for 

 not less than 30 minutes. Technical 

 investigations have demonstrated that 

 the germicidal action of increasing de- 

 grees of heat for longer and longer 

 time periods is progressive in charac- 

 ter ; that is to say, that temperatures 

 substantially below 145 degrees F. 

 have a more and more injurious action 

 upon some of the disease producing 

 bacteria which may be in the milk 

 under treatment, both as the tempera- 

 ture is increased and as the time of its 

 application is prolonged. While the 

 action of these amounts of heat for 

 these periods is progressive in charac- 

 ter, it is the opinion of the Committee 

 that this factor must not be considered 

 as justifying any failure in the opera- 

 tion of any form of apparatus or sys- 

 tem to apply the appropriate degree of 

 heat for the full time period to every 

 particle of the product. In other 



