THE MILK IN ITS RELATION TO CHEESE 23 



Since bacteria cause various kinds of fermentation, not 

 only in the milk but in the products manufactured from 

 it, the question of their control is of prime importance. 

 There are two ways in which the bacterial growth in milk 

 used for cheese-making may be controlled: (1) pre- 

 vention of infection ; (2) the retardation of their develop- 

 ment when present. The former is accomplished by strict 

 cleanliness, the latter by adequate cooling. 



36. The cow. The body of the cow may be a source 

 of bacterial contamination. Bacteria adhere to the hair 

 of the animal, and to the scales of the skin, and during 

 the process of milking these are very liable to fall into 

 the milk. To prevent this, the cow should be curried to 

 remove all loose material and hair. Just before milk- 

 ing, the udder and flank should be wiped with a damp 

 cloth ; this removes some of the material, and causes the 

 remainder to adhere to the cow. 



37. Stable air. If the air of the stable is not clean, 

 it will be a source of contamination. Particles of dust 

 floating in the air carry more or less bacteria, and these 

 fall into the milk during the process of milking. To 



bacteriological content of milk, Edinburgh and East of Scotland 

 Coll. of Agr. Kept. XXVIII, 1913. 



Prucha, M. J., and H. M. Weeter, Germ content of milk, 

 111. Exp. Sta. Bui. 199, 1917. 



Harding, H. A., et al., The effect of certain dairy opera- 

 tions upon the germ content of milk, N. Y. Exp. Sta. Bui. 

 365, 1913. 



Fraser, W. J., Sources of bacteria in milk, 111. Exp. Sta. Bui. 

 91, 1903. 



Frandsen, J. H., Care of milk and cream on the farm, Neb. 

 Exp. Sta. Bui. 133, 1912. 



Conn, H. W., The care and handling of milk, Conn. (Storrs) 

 Exp. Sta. Bui. 26, 1903. 



Stocking, W. A., Jr., Quality of milk as affected by certain 

 dairy operations, Conn. (Storrs) Exp. Sta. Bui. 42, 1906. 



