170 Report OF THE CHEMIST OF THE 
The bung should be left out, but a loose plug of cotton may be 
placed in the hole to decrease evaporation and prevent dirt fall- 
ing in. The bung should be left out until 4.5 to 5.0 per ct. of 
acetic acid has formed. 
MANAGEMENT OF ALCOHOL FERMENTATION. 
When the freshly pressed apple juice is at once placed in ordi- 
nary cellars, where the temperature during winter does not go 
below 45° or 50° F., the alcoholic fermentation is complete in 
about six months, assuming that the work is begun in October or 
November; though 80 to 90 per ct. of the alcohol is formed in 
lialf this time or less. By having the fermentation take place at 
a temperature of 65° or 70° F., the time can be considerably re- 
duced ; however it is not desirable to have the alcoholic fermenta- 
tion take place much above 70° F., since the loss of alcohol by 
evaporation is increased. By the addition of yeast to the fresh 
apple juice, the fermentation can be completed in three months or 
less, especially if the temperature is near 65° or 70° F. It is 
suggested that one Fleischmann’s compressed yeast cake, or an 
equivalent, may be used for five gallons of apple juice, if one de- 
sires to use yeast. The yeast cake is stirred with a cup of water 
and after complete disintegration is mixed with the juice. What- 
ever form of yeast is used, it should be fresh. Vinegar or 
“mother ” should never be added to apple juice. 
MANAGEMENT OF ACETIC FERMENTATION. 
When the alcoholic fermentation is completed, it is well to 
draw off the clear portion of liquid, rinse out the cask, replace 
the clear liquid, add two or four quarts of good vinegar containing 
more or less “ mother” and place at a temperature of 65° to 75° 
F. The acetic fermentation occupies from 3 to 18 months or 
more, according to the conditions under which the fermentation 
is carried on. When the apple juice is stored in cool cellars and 
left there until it becomes vinegar of legal standard, it requires 
from 21 to 24 months or even more. When the alcoholic fermen- 
tation is allowed to take place in a cool cellar and the casks then 
removed to a warmer place, the time of vinegar formation may 
be reduced from that given above to 15 to 18 months. Where 
