152 DAIRY TECHNOLOGY 



likely to cause a grainy texture and a low overrun. A 

 lack of sufficient salt causes smeary ice cream. Lumps of 

 butter are also likely to form. 



In the winter, when the freezer is in a very cold room, 

 it is sometimes noticed that an unusually long time is 

 required to freeze the cream. This is undoubtedly due to 

 the low surrounding temperature retarding the melting 

 of the ice. When the melting is delayed, the absorption 

 of heat from the cream is delayed and, therefore, the 

 freezing process is retarded. In the cold room the ice 

 around the freezer does not melt and form brine rapidly; 

 hence, heat can be conducted from the cream only at 

 points where the ice particles are against the can, and 

 this is but a relatively small proportion of the entire area 

 of the can. When brine is formed, it is in contact with 

 the entire surface of the freezing can, and hence conducts 

 the heat from the cream more rapidly. 



To overcome this slow formation of brine, it is recom- 

 mended that some water be poured over the ice and salt 

 mixture. Having the ice crushed into very fine pieces 

 will also aid in overcoming this difficulty. 



In the style of freezers in which the brine system is 

 employed, the same general principles apply. The mix- 

 ture of ice and salt must be in the proper proportion to 

 produce a brine of such temperature that the cream will 

 be frozen in the proper length of time to insure good qual- 

 ity of ice cream. Under average conditions a mixture of 

 one part of salt to fifteen of ice will produce a brine of 

 about 10 F., and will do satisfactory work in the freezer. 

 Many brine freezers are provided with a compartment for 

 this purpose, and the brine circulated by means of a pump 

 driven by the shaft that drives the freezer. Factories 

 equipped with artificial refrigeration commonly have a large, 



