4 A DAIRY LABORATORY GUIDE 



the products of milk, such as the various kinds of 

 cheese. It is also used commercially in many- 

 ways, some of them being as a substitute for cel- 

 luloid in the manufacture of buttons and toilet 

 articles. It is also used in cold water paints. By 

 a new process it is said that casein is now being 

 made into a substitute for ivory, making excellent 

 table tops, mantels, etc. 



Sugar forms about t^J per cent to 39 per cent of 

 the milk solids. The chief value of milk sugar is 

 its food value in milk. It is also used in pharmacy 

 in mixing powders, coating pills, etc. Milk sugar 

 is not used very extensively commercially because 

 of the expensive cost of manufacture. It is not 

 as sweet as cane sugar, because it is not as soluble. 

 It has the same chemical formula (C12H22O11) 

 as cane sugar. Acid is produced naturally in milk 

 by the action of bacteria upon the milk sugar. 



The albumen in milk is in solution. It is valu- 

 able chiefly as a food in milk. It has one commer- 

 cial use in the manufacture of Italian cheese. This 

 cheese is made where large quantities of whey are 

 produced. The whey is heated nearly to the boil- 

 ing point, and this heat precipitates the albumen. 

 The whey is then drawn oflf and the albumen is 

 dipped into molds. The cheese made from albumen 

 forms a very good, nutritious food. 



The ash is the part of milk left after burning, and 

 it is the most constant constituent of the milk. 

 It very rarely goes below .68 per cent or above .72 

 per cent. It consists chiefly of the phosphates of 

 calcium and the chlorides of sodium, potassium, 

 iron and magnesia. 



Ash is important as a food in furnishing the 

 mineral constituents for the body. 



