No. 6. 



DEPARTMENT OF AGRICULTURE. 



583 



In the case of cream that has been separated by a centrifugal 

 machine, it is important to cool the cream to 50 degrees F. or below, 

 without delay, and to hold it at this temperature for six or eight 

 hours. This cooling appears to be important, in order to obtain 

 butter with sufticiently firm texture. In general, it may be said that 

 we shall be most successful in making butter having the best texture, 

 when the milk and cream are subjected to the fewest changes of 

 temperature and when the changes of temperature that are needed 

 are made in the most gradual, uniform manner. 



After having the cream in the condition indicated above, we per- 

 form the following different operations in making butter: 



(1.) Ripening the cream. 



(2.) Churoing. 



(3.) Washing and working. 



(4.) Salting. 



(5.) Packing. 



After considering the composition of butter, we will take up, 

 in their proper order, the different operations required for making 

 butter. 



25. Composition of Butter. 



The composition of butter varies considerably, according to the 

 methods and conditions of manufacture. The principal variations 

 are in the fat and water. The following tabulated statement serves 

 to give an idea of the usual limits of variation in composition of 

 American butters, but there are extreme cases lying outside the 

 limits here given: 



Good commercial butter should contain over 80 per cent, of fat, 

 and not more than 15 per cent, of water or 3 per cent, of casein. 



26. Ripening Cream for Butter-Making, 



The ripening of cream is essentially the process of developing 

 enormous numbers of certain kinds of bacteria in cream, the most 

 prominent ones in point of numbers and visible activity being lactic 



