WHEY. 



363 



The author has found the fat in whey to vary from 0'04 per 

 cent, (from skim milk) to 1"35 per cent., and ttie solids not fat 

 to lie between 6 and 7 per cent., averaging 6 '6 per cent., which 

 contain — 



Milk-sugar, 

 Protein, 

 Ash, . 



5-0 per cent. 

 1-0 „ 

 0-6 „ 



On adding an acid to whey, a slight protein precipitate (which 

 is difficult of filtration) is obtained. On heating the acid whey, 

 a soft curd of little consistency is formed ; this substance is a 

 commercial article on the Continent. 



The composition of the whey and the precipitated curd (after 

 acidifying and boiling) are given : — 



TABLE XCI. 



On boiling whey without acidifying, a precipitate of a similar 

 nature also occurs ; this appears to consist of coagulated albumin. 



Cheese is sometimes prepared by allowing the milk to become 

 sour spontaneously, salting and pressing the curd, and allowing 

 it to ripen. This variety of cheese is not considered of such 

 good quality as rennet cheese. 



Fleischmann gives the composition of the whey thus obtained 

 as follows : — 



Water . . . 93-13 percent. 



Fat 0-12 



Milk-sugar, .... 4-38 



Protein precipitated by acetic acid, 0-47 



„ ,. tannin, 0-59 



Ash, 0-82 



Difference (lactic acid ?). . . 0-49 



Vieth has shown that whey prepared in this way undergoes- 

 alcoholic fermentation much more readily than rennet whey. 



