104 CONDITIONS AFFECTING RICHNESS OF CREAM 



3. Speed of separator 



4. Rate of inflow 



5. Temperature of milk 



6. Amount of water or skim milk used to flush the bowl 



7. Cleanliness of separator bowl. 



Effect of Cream Screw or Skim Milk Screw on Richness 

 of Cream. The relation of the position of the cream screw and 

 skim milk screw to the proportion of cream to skim milk and to 

 the richness of the cream has been previously discussed. 



Fundamentally, any change in the separator which will alter 

 the relative amounts of skim milk and cream will influence the 

 per cent of fat in the cream. 



These (Jevices, the skim milk screw and the cream screw are 

 very sensitive adjustments. Only a slight turn (J turn) of 

 the screw is sufficient to bring about a very appreciable change 

 in the per cent of fat of the cream. 



Effect of Richness of Milk on Richness of Cream. The 

 richness of the milk separated, directly influences the richness 

 of the cream,; in fact the per cent of fat in the cream stands 

 in direct proportion to the per cent of fat in the milk separated. 



With the cream screw set to deliver a certain definite rich- 

 ness of cream and all other conditions normal, the separator 

 will deliver a definite ratio of skim milk to cream. This ratio 

 varies with the adjustment of the cream screw or skim milk 

 screw. For illustration, it is assumed that this ratio of skim 

 milk to cream be 85 to 15, that is, that of each 100 pounds of 

 milk separated, the separator discharges 85 pounds of skim 

 milk and 15 pounds of cream. If all conditions are the same 

 this ratio of skim milk to cream remains constant. Changes 

 in the richness of the milk cannot alter it, no matter how rich 

 or how poor the milk, each 100 pounds of milk will yield 85 

 pounds of skim milk and 15 pounds of cream. But since prac- 

 tically all of the fat goes into the cream, the cream from the 

 separation of rich milk contains more fat than that from poor 

 milk. This fact is graphically illustrated in Fig. 12. 



