204 



MILK AND DAIRY PRODUCTS PART 



surfaces of the cylinders to a thin paper-like skin, and is scraped 

 off by knives which are fixed alongside the cylinders. Thus, in 

 this method, a vacuum is not employed. The dried milk, after 

 being scraped from the cylinder, is immediately ground to 

 powder. Although the temperature of the cylinder is 130-140, 

 the dried milk is not raised to a higher temperature than 100, 

 for it does not remain sufficiently long in contact with the hot 

 metallic surfaces to allow of all the water being driven off. 



In the two processes described above, the product is made 

 from whole milk, and therefore some addition must be made to 

 the milk before drying, in order to give a greater stability to 

 the emulsion which is formed on dissolving the powder in 

 water. For this purpose Hatmaker uses 1-3 per cent, sodium 

 bicarbonate, and Ekenberg 2 per cent, sugar. Such milk 

 powder made from whole milk soon becomes rancid if air has 

 access to it, but when packed in hermetically sealed tins or 

 pressed into tabloids, it is very durable. In the following 

 table are some data regarding the chemical composition of both 

 these varieties of desiccated milk. 



Milk tabloids are made by simply pressing together the dried 

 milk, and naturally, from the practical point of view, this form 

 is the most advantageous. 



In addition to the preparations of milk which have been 

 described above, there are plenty of others which are used for 

 special dietetic purposes. Amongst these are the two 



1 With 2-5 per cent. fat. 



