204 APPENDICES. 



tion of milk products shall be pasteurized in accordance with the follow- 

 ing regulations : 



(A) Continuous Pasteurization.] In all continuous pasteurization the 

 milk and cream shall be heated to a temperature which shall be deter- 

 mined and fixed by the Department of Health for each machine at a 

 point corresponding to the temperature required to kill 99 per cent of 

 the bacteria and all pathogenic bacteria contained in the raw product. 

 For this determination ordinary raw milk containing in the neighbor- 

 hood of 3,000,000 bacteria shall be used and the pasteurized product shall 

 be collected as it flows from the cooling apparatus. 



All continuous pasteurizers shall be equipped with a feeding pipe 

 which is so constructed that the pasteurizer cannot be fed in excess of 

 its normal w-orking capacity ; that is, in excess of the working capacity 

 of the machine at which 99 per cent of the bacteria are killed when the 

 required amount of heat is applied. 



All continuous pasteurizers operated outside of the city limits, for the 

 production of pasteurized milk and milk products to be sold in the City 

 of Chicago shall be equipped with an apparatus regulating automatically 

 the supply of steam and heat, so as to correspond with and produce the 

 required temperature of the outflow of the pasteurized product. These 

 automatic thermo regulators shall be accurate and must be approved by 

 the Commissioner of Health before being installed. 



A recording apparatus shall be installed upon all continuous pasteur- 

 izers operated within the city limits so as to record during operation the 

 temperature of the pasteurized product as it flows from the heater. The 

 thermometer of this recording apparatus must be accurate and kept 

 emerged in the milk in such a way that it is not exposed to escaping 

 steam or other heat, except the heated milk. 



The records made by this recording thermometer must be accurate and 

 made in a chamber which is kept under lock and key in the control of 

 the Department of Health. 



The automatic thermo regulating and recording apparatus may be com- 

 bined into one instrument and it is recommended that all pasteurizers be 

 equipped with both appliances or the combination apparatus. 



(B) Held Pasteurization.] Whenever milk is held during pasteuri- 

 zation in such a manner that the process of pasteurizing is not a contin- 

 uous one, namely, a continuous flow of milk through the heating or heat 

 retaining chamber, the process shall be designated as ' ' Held Pasteuriz- 

 ation." Such methods of pasteurization and pasteurization appliances or 

 systems installed and used shall be examined and approved by the Com- 

 missioner of Health, or his duly appointed representatives, when all of 

 the following requirements are fulfilled : 



1. When the pasteurized product shows that over 99 per cent of the 

 bacteria and all pathogenic bacteria contained in the raw product have 

 been destroved. 



