MILK 295 



"I wish I could have seen the face Emile made," 

 said Jules, "when he saw the result of his improve- 

 ment. ' r 



"I was much surprised, I admit," Emile rejoined, 

 ' ' to find how two things, orange juice and milk, each 

 excellent by itself, could make such a nasty drink 

 when mixed." 



"In future, my friends, you will know that any- 

 thing sour makes milk turn. What I brought about 

 with lemon juice you effected with orange, which 

 contains, though in small quantity and masked by 

 the sweet flavor of the fruit, exactly the same ingre- 

 dient that gives the lemon its sour taste. 



i l The juice of sorrel leaves, that of green grapes, 

 and of unripe fruits in general, vinegar, and in fact 

 everything with a similar taste, make milk turn at 

 once. These soul-tasting substances are called 

 acids. Vinegar is an acid; that which gives its sour- 

 ness to the lemon is another; green grapes contain a 

 third; sorrel leaves furnish a fourth. The number 

 of acids is very considerable. All those that we 

 need to know anything about have this same sharp 

 flavor, sometimes stronger, sometimes weaker; all, 

 in short, make milk curdle just as I showed you with 

 the acid of the lemon. 



"From theory let us turn to practice. Cleanli- 

 ness in everything is of the first importance, but in 

 the care of milk especially must one be scrupulous 

 in this particular. The vessels for holding it and 

 keeping it any length of time must be carefully and 

 thoroughly cleaned as often as they are used, if one 



