Pasteurization of Milk 



nance required the approval of plans 

 on the building or that part of the 

 building intended for pasteurizing milk 

 or cream. The city ordinances cover- 

 ing pasteurization varied in practically 

 every detail. This was especially 

 noticeable in regard to the tempera- 

 ture and holding period required for 

 pasteurization by the holding method. 

 The temperature requirements ranged 

 from a minimum of 140 degrees F. to a 

 maximum of 165 degrees F., the holding 

 period from 20 to 30 minutes, and the 

 temperature to which the milk should 

 be cooled \ifter holding from 45 to 50 

 degrees F. 



(4) Definitions of Pasteurization. A 

 questionnaire was sent to four depart- 

 ments of the United States Govern- 

 ment and to every state board or de- 

 partment of health in the United States 

 asking whether they had officially de- 

 fined the pasteurization of milk. Three 

 of the Federal departments replied 

 that their departments had officially 

 defined pasteurization and* furnished 

 definitions covering the process. Each 

 department defined the holding method 

 of pasteurization. All of the defini- 

 tions differed as to the wording of the 

 temperature and time requirements 

 which made them substantially at 

 variance when applied to the control 

 of the process. Thirty-seven states 



' replied to the questionnaire, and of this 

 number ten reported that pasteuriza- 

 tion had been defined in their respect- 

 ive states. An analysis of these defi- 

 nitions showed that only two states 

 had nearly uniform definitions while 

 the others varied as to temperature 

 and time requirements. It is apparent 

 from the foregoing statements that 

 there is very little uniformity in the 

 Federal and the state definitions of 

 pasteurization in this couritry. 



(5) Apparent Lack of Control and 

 Uniformity of Methods. It appears 

 from the information obtained on the 

 state and municipal control of pasteur- 



ization plants, that in general there is 

 very evident lack of supervision from 

 a health point of view. There are 

 some instances where it would appear 

 that active steps are taken towards 

 control, but in many cases, through 

 lack of legal authority, appropriations, 

 or organization, the work is not satis- 

 factorily carried out. In state work 

 there are a number of instances where 

 there is an apparent lack of co-ordina- 

 tion of the activities that make pos- 

 sible the proper supervision of pas- 

 teurization while in many others the 

 public health aspect of the problem 

 has not been given any consideration. 

 The lack of uniformity in the defini- 

 tions of pasteurization throughout the 

 United States leads to needless confu- 

 sion and controversy which could be 

 obviated by establishing a definite 

 standard. 



(6). Absence of Public Understand- 

 ing of Pasteurization. There is quite 

 an evident lack of understanding on 

 the part of the public regarding the ac- 

 tual meaning of pasteurization at the 

 present time. Investigations, in one 

 state, where an intensive survey of 

 milk pasteurization has been under- 

 taken during the past year, show that 

 many health authorities are generally 

 accepting any kind of heat treatment 

 as a satisfactory health measure,' while 

 in many of these instances the process 

 is being carried on to prevent the 

 souring of the milk and for advertis- 

 ing purposes rather than to improve 

 the sanitary quality of the milk. There 

 is a very obvious need for an educa- 

 tional campaign to enlighten the pub- 

 lic on the meaning of milk pasteuriza- 

 tion. 



III. The Effect of Pasteurization on 

 the Composition of Milk. 



In the early days of pasteurization, 

 disagreement prevailed among those 

 conversant with the subject, regard- 

 ing the effect of heat on the variovis 



