FROM THE PRACTICAL VIEWPOINT 



high in temperature, there is a certain amount of 

 danger of cooking or scorching the milk, and pos- 

 sibly of breaking up the fat globules. It is also 

 true that if a coating of cooked milk forms on the 

 inner surface of the tube, it acts as an insulating 

 material and therefore a constantly increasing tem- 

 perature must be applied to the water. The return 

 of the milk from one tube to another in the series 

 tends to mix the milk and so break up the more 

 rapid flowing core. This breaking up process, 

 however, may have a detrimental effect upon the 

 fat content and may render the cream less likely 

 to rise. In one or two instances known to the 

 writer it was found that when the milk left the 

 apparatus at a temperature of only 140 the cream 

 line was considerably interfered with. 



The types shown in Figs. 7, 10 and 11 have this 

 advantage, namely, that since they can be obtained 

 in sections, the pasteurizing plant can be expanded 

 by the installation of additional sections as the 

 growth of the business demands. Since a cooling 

 apparatus of exactly similar form is provided it is 

 possible to extend the cooling facilities in the same 

 way. By a proper interchange of the water used 

 in both the heater and cooler, the regenerative 

 63 



