Bacteria in Market Milk. 209 



In order to conform to these requirements, a heavy ex- 

 penditure must be incurred, and the business must pay 

 for such expert service ; hence, certified milk must be 

 sold at high prices, twelve to twenty-five cents per quart. 

 This price makes it a special product and its use is con- 

 fined mainly to infant feeding. 



Tlie bacterial standard for certified milk is usually 

 10,000 bacteria per cubic centimeter. It is only by the 

 exercise of the greatest care at every point that the bac- 

 terial content can be kept below this maximum. 



The term "certified milk" has been registered by Mr. 

 Francisco of New Jersey, who was the first to engage in 

 the production of such milk under the direction of the 

 Medical Milk Commission of Essex County, New Jersey. 

 The use of the term is allowed when the milk is produced 

 under the regulation of any Medical Milk Commission. 



Most certified milk is now produced on fancy dairy 

 farms conducted by wealthy men. The barns and other 

 equipment are the best that can be obtained, and the 

 methods employed, as far as cleanliness is concerned, are 

 extreme. In some of the dairies the bacterial content is 

 reduced to a few hundred per cubic centimeter, or to 

 that which is derived from the interior of the udder. 

 Such milk will, when well refrigerated, keep for long 

 periods of time. It is a not uncommon thing for such 

 milk to keep perfectly sweet for ten to fifteen days. 



Tests for the quality of milk. At the milk depot and 

 elsewhere, it is frequently desired to determine the bac- 

 terial condition of the milk in a less refined manner than 

 by the plate cultures of the bacteriologist, which require 

 a large amount of time for their preparation and do not 

 yield any positive information for at least twenty-four 

 hours. There are a number of such tests that may be 

 applied. 

 14 



