Contamination of Milk. t 25 



considerable one, but the quality of the factory by-product 

 for feeding purposes, whether it is skim-milk or whey, is 

 impaired through the development of fermentative changes. 



Improved methods of disposal of by-products. The diffi- 

 culties which attend the distribution of these factory by- 

 products have led to different methods of solution. One is 

 to use another separate set of receptacles to carry back 

 these products to the farm. This method has been tried, 

 and while it is deemed impracticable by many to handle two 

 sets of vessels, yet some of the most progressive factories 

 report excellent results where this method is in use. 



Large barrels could be used for this purpose to econo- 

 mize in wagon space. 



Another method that has met with wider acceptance, 

 especially in creameries, is the custom of pasteurizing or 

 scalding the skim-milk immediately after it is separated, 

 so that it is returned to the farmer in a hot condition. In 

 factories where the whole milk is pasteurized, further 

 treatment of the by-product is not necessary. In most 

 factories steam, generally exhaust, is used directly in the 

 milk, and experience has shown that such milk, without 

 any cooling, will keep sweet for a considerable number of 

 hours longer than the untreated product. It is noteworthy 

 that the most advanced and progressive factories are the 

 ones that appreciate the value of this work, and although 

 it involves some time and expense, experience has shown 

 the utility of the process in that a better grade of milk is 

 furnished by the patrons of factories which follow this 

 practice. 1 The exclusion of all danger of animal or human 

 disease is also possible in this way. 



i McKay, N. Y. Prod. Rev.. Mch. 22, 1899. 



