DAIRY HUSBANDRY 
89 
EXERCISE NO. 12 
Object: To determine the effect of the rate of inflow into the bowl on the effi¬ 
ciency of separation, the relative amount of cream and skimmilk 
and on the test. 
Procedure: Some objections to farm separation of cream are made be¬ 
cause the quality of farm skimmed cream suffers due to im¬ 
proper location of separator, infrequent washing, improper 
cooling of cream, and infrequent deliveries, and because of the 
extra time and power required to operate the separator. 
A. Obtain 30 or 40 pounds of milk and divide into two equal parts. 
Skim part one at a temperature of 90° F. with the separator 
running at normal speed, and the supply valve wide open. 
Skim the second part at 90° F. with the separator running at 
normal speed but with the supply valve only half open. 
Follow the directions given in Exercise 8. 
Note: Shift the class so that each member fills a new position. 
Observations: Machine.No.Capacity.. 
(1) Weight of milk . 
(2) Test of milk . 
(3) Pounds of fat . 
(4) Pounds of cream . 
(5) Test of cream. 
(6) Pounds of fat in cream . 
(7) Pounds of skimmilk . 
(8) Test of skimmilk . 
(9) Pounds of fat in skimmilk . 
(1) Fat unaccounted for . 
(11) Per cent cream is of milk . 
(12) Length of test in minutes . 
(13) Capacity . 
(14) Speed of bowl .... . 
(15) Temperature of milk. 
Conclusions: 
Questions: (1) What are the advantages of centrifugal separation to the 
farmer? 
(2) Give reasons for inefficient skimming of a separator. 
(3) Where should a farm separator be located? 
(4) How is the approximate length of time that the milk remains 
in the separator bowl calculated? 
References: Jud. pp. 180-192; St. pp. 224—236. 
