142 Condensed Miek and Milk Powder 



DEFECTIVE SWEETENED CONDENSED MILK 



The following are the chief and most common defects of 

 sweetened condensed milk: 



i. Sandy, rough or gritty 



2. Settled 



3. Thickened and cheesy 



4. Lumpy, white or yellow buttons 



5. Blown or fermented 



6. Rancid 



7. Putrid 



8. Brown 



Sandy, Rough or Gritty Sweetened Condensed Milk 



General Description. — This is condensed milk in which a 

 portion of the milk sugar has been precipitated in the form of 

 crystals, the size of the crystals depending on the conditions causing 

 crystallization. First-class sweetened condensed milk is smooth and 

 velvety. Such milk is not entirely free from sugar crystals, but 

 they are so minute in size that they do not rob the condensed milk 

 of its natural smoothness. In sandy or gritty condensed milk the 

 crystals are very numerous and large enough to grind between the 

 teeth, similar to salt crystals in gritty butter. The presence of these, 

 crystals is also noticeable to the naked eye; the milk looks candied. 



Causes and Prevention. — 'The sugar crystals which render 

 the condensed milk rough and sandy consist largely of milk sugar. 

 The solubility of milk sugar is relatively low. Milk sugar requires 

 about six times its weight of water at ordinary temperature for 

 complete solution. Condensed milk contains from 12.5 to 15 per 

 cent, milk sugar and only about 26.5 per cent water. The ratio of 

 milk sugar to water in sweetened condensed milk, therefore, is 1 :2, 

 while for complete solution it should be 1 :6. The milk sugar in this 

 product is present in a supersaturated solution and any condition 

 which favors sugar crystallization strongly tends to precipitate this 

 milk sugar, because there is more of it present in the milk than the 

 available water is capable of readily keeping in solution. The chief 

 factor that prevents the milk sugar from precipitating very badly 

 is the great viscosity of the condensed milk. This is largely due to 

 the caseous matter and the cane sugar. 



