INIECIIAXTCAL RKI-KK.I^KAIK )X ?>lo 



Some open vats have a jacket and special <jpen space at one 

 enci for holding crushed ice. These \'ats will control and hold 

 temperature better than those that simply ha^'e a jacket around 

 them. The cooling of cream on a large scale by circulating ice- 

 water through the jacket is, at best, a slow process, usually too 

 slow to be effectiA-e and practical. 



This cooling process is carried out by mixing the ice and 

 water together in a separate vat to which a rotar\' pump is 

 attached, forcing the water through the jacket and again return- 

 ing it to the ice and water-tank to be cooled. The slowness of 

 this cooling process can in a measure be overcome by niLxing salt 

 with the ice and water. This will cause the ice to melt faster, 

 and consequently cool the brine to a lower degree of temperature 

 than it is possible to obtain with water and ice. 



In case it is desirable, a set of coils can be made which will 

 fit into the open vat. The inlet and outlet of these coils can be 

 connected b}' means of rubber hose with the pipes conve\-ing the 

 brine to and from the ripener. The coils can be made to moA'e 

 up and down, by means of a rope attached to and leading from 

 the coils through a pulle}' near the loft and fastened to a small 

 crank at the end of a shaft. When the shaft turns the crank 

 will also turn and cause the coils in the vat to moA'e up and down. 

 In the absence of a special up-to-date ripener, this manner of 

 cooling works ver)- satisfactorily. 



A butter refrigerator containing a tank, as already described, 

 could be cooled by pumping brine through it in a similar 

 manner, as described for cream cooling, except that no coils are 

 needed. 



MECHANICAL REFRIGERATION 



Application in Creameries. — Mechanical refrigeration on a 

 small scale has been considered expensive and impracticable 

 until within recent }-ears. The science of producing cold arti- 

 ficially has been simplified and reduced to such a practical 

 basis that it is now used in man}' large plants as well as in smaller 

 plants where formerl}' natural ice was used altogether. Where 

 at least 10,000 pounds of milk, or its equivalent in cream, 



