130 



EVAPORATED MILK COOUNG 



is advisable to cover the coils with a jacket of galvanized iron, 

 tin or copper, so as to avoid undue contamination of the milk 

 from dust, flies, and other undesirable agents. In so~? oon- 

 denseries trie hot evap- 

 orated milk is forced 

 through double pipes, 

 c'old water passing be- 

 tween the inner and 

 outer pipes, or the coils 

 through which the milk 

 passes are submerged 

 in a tank of cold water. 

 The only objection to 

 this system is that the 

 pipes are more difficult 

 to clean than in the 

 case of an open surface 

 cooler. Where this sys- 

 tem is used, the pipes 



. Tig. 52. Surface cooler for evaporated milk 



should be equipped Courtegy of Davis . Watklns Dairymen > s Mfg . Co . 

 with sanitary fittings 



so that they can be readily swabbed out from both ends. In 

 other factories, the evaporated milk is cooled in revolving cans 

 with stationary paddles, similar as described and used for 

 sweetened condensed milk, with the exception that cold water 

 is run into the cooling tank at once. In still other factories the 

 cooling is done in vats or tanks by means of revolving coils 

 which carry the cooling medium. If the evaporated milk is not 

 homogenized, it should be cooled as soon as it leaves the vacu- 

 um pan. 



Holding Tanks. The cooling and holding of evaporated 

 milk may be accomplished in the same series of equipment as 

 described and illustrated under cooling of sweetened condensed 

 milk, Fig. 38. The tanks for holding this product are preferably 

 jacketed, so as to make possible the circulation of cold water 

 or brine, in case the evaporated milk must be held for a consider- 

 able number of hours in the holding tank. Some of these tanks 

 are equipped with propellers eccentrically located, facilitating 



