PRESENT STATUS OF PASTEURIZATION OF MILK. 7 



From a sanitary standpoint this process is very satisfactory. In the 

 past, on account of the difficulty of treating large quantities of milk, 

 pasteurization in bottles has not been used to any great extent in 

 large plants. 



The bottling of hot pasteurized milk in steamed bottles is a process 

 which eliminates the danger of reinfection and can easily be adapted 

 to the treatment of milk in large quantities. 



Any one of these methods of pasteurization is satisfactory, pro- 

 vided a temperature of 145° F. is maintained for 30 minutes and 

 reinfection is prevented during subsequent handling of the milk. 



SUPERVISION OF THE PROCESS OF PASTEURIZATION. 



As is the case with almost every known process which permits 

 of variation by the operators, the process of pasteurization is fre- 

 quently . performed improperly. This is attributable sometimes to 

 lack of care on the part of the operators, but probably more often to 

 lack of proper knowledge of the functions of the process. Pasteuri- 

 zation calls for supervision by competent inspectors to remedy such 

 conditions, and supervision is provided for in only a few of the 

 larger cities. In these cities the process must be performed by ma- 

 chines approved by the boards of health, and at such temperatures 

 and for such periods of holding as are required. 



In some cities pasteurized milk must be marked " Pasteurized," 

 and in some cases the temperature must be stated, together with the 

 date of pasteurization. 



In most of our cities. there is a great lack of proper control over 

 the process of pasteurization, and a standard method of pasteuriza- 

 tion and definite procedure for proper supervision of the process is 

 greatly needed." 



The process of pasteurization is by no means " foolproof." It 

 demands a knowledge on the part of the operator of the action of 

 the process and its objects. Not all operators have such knowledge. 

 Records obtained in 1912 from 231 milk plants showed that 99 per 

 cent of those which used the holder process pasteurized at the proper 

 temperature. Among those * which used the flash process only 57 

 per cent employed temperatures high enough to give satisfactory 

 results, while in the other 43 per cent the temperatures were too low 

 to be effective in the destruction of pathogenic bacteria. At the 

 present time this condition is much improved. 



Anyone who has had the opportunity to examine the numerous 

 plants where pasteurization is practiced has undoubtedly found cases 

 in which as many bacteria were introduced in cooling and bottling as 

 were destroyed by the heating process. It is in such cases that the 

 operator's ignorance of the fundamental principles of the process is 



