186 VINEGAR, CIDER, AND FRUIT- WINES. 



The vessels are so arranged that the finished vinegar can be re- 

 moved and replaced by wine to be acetified without disturbing 

 the ferment, one being thus enabled to uninterruptedly continue 

 the process of the formation of vinegar for a long time, and pro- 

 ducing vinegar unsurpassed by any other product as regards deli- 

 cacy of taste and odor. According to the above statement, the 

 operation includes the cultivation of the vinegar ferment on a small 

 scale and on a large scale, the former for the production of- pure 

 ferment and the latter for obtaining wine-vinegar. 



The cultivation of pure vinegar ferment on a small scale is 

 best effected by heating wine in a porcelain or glass dish to 140 

 or 150 F., then mixing it with an equal volume of vinegar and 

 pouring the resulting fluid into shallow porcelain plates, which 

 are placed in a warm room. In a short time, generally in 24 to 

 30 hours, the veil-like layer of vinegar ferment previously de- 

 scribed is observed upon the surface of the fluid. If, besides the 

 dull spots which are characteristic of pure vinegar ferment, spots 

 of a pure white color are formed, it is an indication of the devel- 

 opment of mold ferment. The contents of the plates showing 

 this phenomenon have to be boiled and then again exposed to 

 the air. 



The wine to be acetified is in large, shallow vats, and is 

 brought to fermentation by carefully submerging in it one of 

 the above-mentioned plates containing pure vinegar ferment, so 

 that the latter is distributed upon the surface; the plate is then 

 withdrawn. The ferment augments very rapidly, so that, in 24 

 hours, the surface of the wine in the vat is entirely covered with 

 a thin veil of it. By keeping the temperature of the room in 

 which the vats are placed at about 68 F., the acetification of 

 the wine proceeds rapidly, tests repeated at intervals of 24 hours 

 showing a constant increase in the content of acid, until in about 

 8 days all the wine is converted into vinegar and is drawn off. 

 To avoid the necessity of especially infecting the next quantity 

 of wine the finished vinegar is not entirely drawn off, a small 

 quantity (about J to 1 inch deep) upon the surface of which the 

 vinegar ferment floats being allowed to remain in the vat. By 

 now introducing a fresh lot of wine the vinegar ferment propa- 

 gates upon it and after some time converts it into vinegar. 



