180 Condensed Milk and Milk Powder 



will foam very badly in the vacuum pan, which renders the process 

 of condensing a difficult one and the finished product has a bitter 

 flavor. Under ordinary conditions, their use is entirely unneces- 

 sary and simply means additional labor and expense. The above 

 agents and also viscogen, are sometimes used with the view of 

 thickening the product and increasing the output. Experimental 

 results, 1 however, showed that these agents cannot be used in large 

 enough quantities to produce the above results without materially 

 lowering the quality of the product. 



Addition of Cream of Tartar. — Cream of tartar is used ex- 

 tensively in the manufacture of candies and caramels. Its purpose 

 is to make the sugar in these products precipitate in the form of 

 very fine and soft crystals. Condenseries, which have been con- 

 tinually troubled with sugar crystallization and sugar sediment, have 

 tried to overcome this defect by adding cream of tartar to the 

 sweetened milk in the vacuum pan. Cream of tartar is an acid 

 salt (acid potassium tartrate, K'H.'CtH 4 O e ), and it is this acid, 

 which in the manufacture of candy, causes the fine and soft grain 

 of the sugar. It is obvious, that if enough cream of tartar were 

 added to condensed milk, to produce the desired effect on the sugar, 

 the acid present would curdle the milk. Its use is of no value to 

 the manufacturer of condensed milk. 



Addition of Starch. — The pasty and thick consistency of sweet- 

 ened condensed milk frequently suggests to the public that it con- 

 tains starch. This is erroneous, for it is doubtful if condensed 

 milk is ever adulterated with starch. There would be absolutely 

 nothing gained by so doing, and the presence of starch in condensed 

 milk could be readily detected with iodine. Iodine gives the starch 

 cells a deep blue color. 



1 Hunziker. Experiments not published 



