86 VARIATION OF FAT IN MILK AND CREAM 



will deliver 85X300-7-100 or 255 pounds of skim-milk and the 

 remainder, the overflow, will be cream. In this case the amount 

 of cream discharged will be 45 pounds (300 255=45). If the 

 separator is forced beyond its capacity, that is if more than 300 

 pounds of milk are run into the machine, the skim-milk dis- 

 charged remains the same and the cream discharged receives the 

 extra milk. Running 350 pounds of milk into the machine, 

 for example, causes the separator to yield 255 pounds of skim- 

 milk and 95 pounds (350 255 =95) of cream. If the milk inflow 

 is reduced below the capacity of the cream, say to 270 pounds, 

 the skim-milk discharged remains the same (255 pounds) and 

 the cream discharged is 15 pounds (270 255 = 15). The effect 

 of these variations in the rate of inflow on the richness of the 

 cream is shown in Fig. 15. 



The above diagram shows that almost any richness of cream 

 may be obtained from the same milk and the same separator 

 according to the amount of milk that flows into the bowl per hour. 

 A normal inflow produced 26.7 per cent cream, a large inflow 

 produced 14.7 per cent cream and a small inflow produced 

 72 per cent cream. 



Even the fullness of the pan or tank from which the milk 

 runs into the bowl affects the richness of the cream. The fuller 

 the tank the more rapidly will the milk flow into the bowl owing 

 to a few inches of additional pressure. If the tank is kept filled 

 to the brim the cream will be thinner than when the tank remains 

 only one-third full. 



Every separator is equipped with a simple device called the 

 " Float " to regulate the inflow. The float fits into the receiving 

 cup of the bowl. When. too much milk flows into the bowl the 

 float rises and partly shuts off the outlet of the milk supply tank. 

 When too little milk runs into the bowl the float recedes and the 

 supply tank delivers more milk. 



The simplicity of the float has had a tendency to belittle its 

 value in the mind of the average dairyman, with the result that 

 on many farms it is not used and has been discarded. Bearing 

 in mind the marked effect of the rate of inflow on the richness of 

 the cream it seems inconsistent to accuse the creamery of inac- 



