THE MILK CONTRACTOR 305 



actual handling of milk. The inspector, therefore, first carefully examines all 

 pipes and connections, pumps and other apparatus used in handling the milk, 

 taking the various fittings apart, if necessary, to assure himself of their cleanliness. 

 He also watches the sterilizing of pipes and vats before their use, which process 

 serves also to enable the first milk to hold its temperature without undue loss. 

 During the actual handling of milk the inspector notes its condition upon receipt 

 as to dirt, temperature, sweetness, etc., and watches to see that it is not exposed 

 to dust or dirt. The temperature during its pasteurization is recorded automat- 

 ically upon the dial of a clock recorder, the accuracy of which is tested at each 

 inspection. These recording devices will also indicate the holding period in 

 certain forms of absolute holders, but will not perform this function in the case of 

 continuous retarders. In this latter type of apparatus the holding period is 

 best ascertained by watching the speed at which the milk is dumped through 

 them. Upon leaving the holders the milk must be cooled quickly to a low tem- 

 perature, preferably from 40 to 45F. or even lower and then immediately placed 

 in the cans or bottles in which it is to be shipped. The inspector notes the tem- 

 perature of cooling at frequent intervals, and is thereby enabled to advise if the 

 hot milk is fed to the cooler too fast to obtain good results, and have the flow 

 regulated in accordance. The cleanliness of bottles and cans used for holding 

 pasteurized milk is a feature of great importance. The aim of the department 

 is to obtain sterility of containers after they have been cleaned, and here the 

 personal effort of the inspector can often accomplish better results than any pre- 

 scribed set of regulations. Bacteriological examinations of rinsings with a sterile 

 water control is the guide that is followed, and inspectors are kept closely in- 

 formed of all such results. The commonly accepted standard in such cases is a 

 count of 1,000 for bottles and of 40,000 for cans, 50 c.c. of sterile water being used. 



"After pasteurization for the day is concluded attention is directed first to 

 the correct labeling of the milk and its refrigeration pending shipment, and then 

 the important feature of thoroughly cleaning the apparatus. First of all the 

 pipes and pumps must be taken apart and each length or piece washed, scrubbed 

 and rinsed. A plentiful supply of hot water and a liberal use of it is essential. 

 Then after the apparatus is assembled again it "must be sterilized by live steam 

 for at least half an hour. After this is done empty cans and bottles returned from 

 the city are washed, rinsed and steamed in order to be ready for the following 

 day. 



"The schedules of inspection are arranged so as to provide that samples of 

 the milk are taken during inspection of pasteurizing plants at stated intervals. 

 Four samples are taken at each of the various steps and from these four individ- 

 ual samples an average is obtained which fairly reflects the quality of the milk 

 and also serves as a check upon the thoroughness of pasteurization. Usually 

 these samples are taken from (a) the raw milk, (6) at the outlet of the holder or 

 after the milk has been heated and held, (c) from the outlet of the cooler, (d) 

 from bottles or cans that have been filled for shipment. These samples are 

 thoroughly chilled, packed in ice, and shipped in the milk car to the city terminal 

 where they are collected upon arrival and taken to the laboratory. 



"There are so few occasions during inspections of pasteurizing plants that 

 fail to show some defect, serious or trivial, in equipment or operation, and the 

 conjunction of a number of defects trivial in themselves so frequently constitutes 



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