220 MANAGEMENT OF DAIRY PLANTS 



IV. Factors Influencing Yield of Ice Cream Obtained. - 



The principal factors influencing the yield of ice cream obtained 

 are: First, condition and treatment of cream used; second, tem- 

 perature of ice cream when drawn from freezer; third, tempera- 

 ture of circulating brine; fourth, size of batch frozen; fifth, 

 speed of agitator. 1 



1. Condition and Treatment of Cream Used. The value of 

 aging the cream has been formerly discussed. Rich cream pro- 

 duces a higher yield than thinner cream. Cream of a high 

 temperature is likely to churn during the freezing process and 

 the yield is, as a result thereof, decreased. Homogenized 

 cream produces less yield than does cream which has not been 

 so treated unless frozen longer than untreated cream. 2 



2. Temperature of Ice Cream When Drawn from Freezer. 

 The temperature at which the ice cream returns the greatest 

 yield is usually from 27 F. to 28 F. This, however, may vary 

 slightly due to the condition of the cream used. 



3. Temperature of Circulating Brine. A brine of low tem- 

 perature causes the ice cream to freeze before a sufficient 

 amount of air has been incorporated. If the brine is too warm 

 the freezing takes too long and it may result in partly churning 

 the cream. A brine of a temperature from 8 F. to 14 F. is 

 most desirable; the lower temperature is most satisfactory for a 

 cream of lower viscosity. A cream of higher viscosity, such as 

 homogenized cream, should be frozen with a brine of the higher 

 temperature so as to allow longer time for the incorporation 

 of air. 



4. Size of Batch Frozen. The larger the batch up to a cer- 

 tain limit the greater the yield will be. The smaller batch 

 freezes too soon before a sufficient amount of air has been 

 incorporated. 



5. Speed of Agitator. The freezer should be operated very 

 slowly until it reaches the point of freezing which varies from 

 28 F. to 29 F. 3 It should be the object to reach that point 



1 Bulletin 180, Iowa Experiment Station, 1918. 



2 Bulletin 180, Iowa Experiment Station, 1918. 



3 Bulletin 155, by Washburn, Vermont Exp. Station, 1910. 



