BACTERIOLOGICAL STUDIES OF MILK SUPPLIES 



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the number is 500,000, for Rochester 100,000. In each case this 

 limit is the maximum limit. They do not say that the milk is fit for 

 infants and invalids, but have another standard for such milk and call 

 that milk certified milk. Now naturally we might assume that, under 

 conditions as found in and about Boulder, with its oft proclaimed pure 

 air, the counts should all come well within 100,000 — the limit set for 

 Rochester, a city of 218,000 population. Yet a perusal of Chart I will 

 show that only twelve of the twenty-one come within this, and further- 

 more, of these twelve only five were made during the summer months, 

 the other seven being made during December and January. There is 

 quite a strong possibility that some of the seven made in the winter 

 might not have made a good showing during the summer months. 



CHART V 



Colorado Springs has established no arbitrary standard, yet a 

 good milk is considered to be one containing under 100,000 bacteria 

 per cubic centimeter, with certified milk 10,000 per cubic centimeter 

 in winter and 20,000 in summer. 



Most of the samples taken during the winter show a reasonably 

 wholesome milk from the bacterial standpoint. This suggests that 

 the trouble may be in neglect in proper cooling of the milk during the 

 warm months, for it is well known that unless the milk is rapidly and 

 sufficiently cooled, very soon after milking, the filth bacteria which 

 have entered at this time will reproduce to an enormous extent. 



