FABRICATION OF WINE- VINEGAR. 183 



defects from beginning to end. The acidulation of the casks with 

 boiling vinegar is simply preposterous, because by heating the 

 vinegar and pouring it boiling hot into the cask not only the 

 vinegar ferment contained in it is destroyed but also that present 

 in the cask or wine itself. That acetous fermentation takes place 

 notwithstanding is very likely due to the following causes : 



The hot fluid in the cask gradually cools off and is finally re- 

 duced to the degree of temperature most favorable to the develop- 

 ment of the vinegar ferment ; in the same proportion as cooling 

 off takes place the air contracts in the cask and air enters from 

 the outside. The latter, however, carries with it germs of vinegar 

 ferment which rapidly develop upon the fluid when reduced to the 

 proper temperature and cause its acetification. The air pene- 

 trating into the cask may, however, accidentally contain no vine- 

 gar ferment, or that contained in it may not reach the wine ; in 

 such case the wine may for weeks remain in the cask without any 

 perceptible acetification taking place until the latter finally ap- 

 pears by an accidental development of the vinegar ferment. This 

 uncertainty can, however, be readily avoided by the direct culti- 

 vation of the vinegar ferment- upon the wine to be acetified. 

 Milk, as is well known, turns sour on exposure to the air by the 

 milk sugar being converted into lactic acid by the action of a 

 ferment frequently occurring in the air, this souring taking place 

 in several hours or several days according to the temperature to 

 which the milk is exposed. It is further a well-known fact that the 

 addition of a few drops of sour to sweet milk suflices to imme- 

 diately induce the formation of lactic acid in the latter ; the fer- 

 ment of lactic acid fermentation being in the true sense of the word 

 sowed upon the milk. The ferment develops very rapidly, con- 

 verts the sugar into lactic acid, and in a short time turns the en- 

 tire quantity of milk sour. 



Exactly the same course may be pursued as regards the vinegar 

 ferment, it being only necessary to mix the wine with a fluid 

 containing living vinegar ferment and place it in a sufficiently 

 warm room in order to immediately start the process of the 

 formation of acetic acid ; in this case the vinegar ferment is 

 sowed upon the wine, or, in other words, the wine is infected with 

 vinegar ferment and intentionally made " sick." This method of 



