SWEETENED CoNDENSED MiLK—COooLING 107 
the concentration is in excess of that desired, the product is 
standardized by the addition of the accurately calculated nec- 
essary amount of distilled water. 
From this stand- 
ardizing tank the hot 
condensed milk 1s 
forced by means of the 
high pressure pump 
through the submerged 
coil in the cooling tank. 
The water supply to 
this tank is automati- 
cally regulated by a 
; Fig. 37. thermostat, so as. to 
High pressure pump for sweetened condensed 
milk cool the condensed milk 
Courtesy of Union Steam Pump Co. to the desired tempera- 
ture (usually 65 to 75 degrees F.). 
The condensed milk remains in the submerged coil about 
six minutes, 1. @, six minutes elapse from the time it enters 
the coil till it reaches the exit. From here the now cool con- 
densed milk flows to the holding tank where it is slowly agitated 
for several hours. 
Experience has demonstrated that this method of cooling 
and agitating sweetened condensed milk is very effective in 
preventing the production of sandy and settled milk. It appears 
that the great viscosity of the sweetened condensed milk causes 
the milk, in its passage through the coil, to be subjected to the 
least damaging agitation. ‘The center of the column of the 
milk moves forward slightly faster than the portion nearest the 
walls of the coil. This results in a rolling or curling motion, 
producing sufficient and vet not excessive agitation. 
The subseqent slow agitation of the cooled condensed milk 
in the holding tanks for a considerable period of time, further 
assists in the preservation of a smooth product. It enhances 
the formation of very small crystals at the expense of larger 
crystals, thereby minimizing the tendency toward coarseness and 
insuring a uniformly smooth product that is not prone to vield 
a sugar sediment. 
