QUANTITY OF MILK CREAMED PER HOUR. 145 



proper revolving rate only where the handle is properly turned. 

 The hand-separators whose drum is turned by means of friction 

 (the hand-separators with falling drums, the Arnold, De Laval, and 

 the Alpha hand-separator K) should not be used without an indicator. 



For exact scientific experiments indicators are necessary, such as those 

 of Schaffer and Budenberg indicators which record exactly the number 

 of revolutions made by the separator-drum throughout a comparatively 

 long period. 



72. The Supervision of the Quantity of Milk Creamed per Hour. 

 Very different quantities of milk may be creamed per hour, in different 

 separators, and variable quantities of skim-milk, containing different 

 percentages of fat, may similarly be obtained. In a well-ordered 

 dairy the aim is to obtain daily an equal quantity, viz. the largest 

 possible quantity of fat. In order to obtain this, the milk has to be 

 poured into the drum at an equable rate ; and secondly, the quantity 

 of milk creamed should be creamed in such a way that the desired 

 coefficient of cream-raising should be obtained. The first condition 

 can be satisfied, at any rate approximately, by the use of vessels 

 with floats. A good vessel should also be arranged in such a way 

 that one can limit the rate at which the milk runs out, so as to be 

 able to increase or diminish the quantity running out in the course 

 of an hour. 



The measure of the rate at which milk runs out is discovered 

 by estimating the amount of milk which is daily creamed per hour. 

 The percentage of fat in the skim-milk is also determined. Should 

 it be found that the coefficient of creaming is unsatisfactory, the 

 rate at which the milk runs in ought to be diminished, until the 

 skim-milk flowing away shows a percentage of fat of about '25. 



The amount of milk creamed per hour is determined as follows: 

 When the drum has obtained its full speed, and creaming is ready to be 

 started, the hour, minute, and second are noted, at which the cock of the 

 warmer or of the collecting vessel is opened ; and again, the time at which 

 the last of the milk passes through the cock. The interval is that during 

 which the whole quantity of milk runs through the drum. For example, 

 if from 6-17 till 9*32 that is, 3 hours 15 minutes, or 195 minutes, 260 

 kilos, exactly of milk passed through the drum of the separator, the 

 amount of milk which would be creamed in an hour would be 



2600 x 60 QAA , ., 

 = 800 kilos. 

 195 



(M175) K 



