MILK POWDER 



269 



ing, etc., of the milk-powder starters were all carried on 

 in the same manner as when fresh-milk starters were 

 made and the results secured by the use of milk-powder 

 starters were as good as those when fresh-milk starters 

 were used. 



Milk powder is used in the preparation of commercial 

 cultures of lactic-acid bacteria, the culture material being 

 mixed with sterile-milk powder, bottled and distributed 

 for use in butter and cheese factories. In this medium 

 the lactic bacteria retain their vitahty for more than a 

 year. 



Composition. — Three kinds of milk powders are manu- 

 factured: whole-milk powder, half-skimmed- milk powder 

 and skirmned-milk powder. The butter fat in the whole- 

 milk powder interferes with its keeping properties. 



The composition of these dried milks is as foUows: 



Whey Powder or Dried Whey. — Whey is reduced to 

 a powder by exactly the same process as that employed 

 in the reduction of milk to powder. This powder is 

 used in the diet of infants and invalids, in cases where 

 the presence of casein interferes with proper digestion. 

 Many dietary formulas call for whey as one of the ingre- 

 dients. Fresh whey is not always obtainable, but whey 

 powder may be kept on hand at all times and is ready for 

 use upon the addition of water. 



