136 REPORT OF THE CHEMIST OF THE 
10. Cider Vinegar in Relation to Legal Standards.—Legal 
standards for cider vinegar are usually based upon the percentage 
of acetic acid and cider-vinegar solids. In New York State, 
the legal requirement is 4.5 per ct. of acetic acid and 2 per ct. of 
solids. From our work, it appears that where proper fruit is 
used for cider-making and where the conditions of fermentation 
are properly controlled, there should be no difficulty in making 
cider vinegar that contains above 4.5 per ct. of acetic acid in 18 to 
24 months. 
In respect to the requirement of 2 per ct. of cider vinegar 
solids, something depends upon the method of determining solids, 
since there is yet no recognized official method. It would be 
wise for the law to fix the method to be used in estimating 
solids. 
11. Conditions commonly producing Cider Vinegar below 
Standard.—The more common causes responsible for the produc- 
tion of cider vinegar low in acetic acid are the following :—(1) 
Poor apple juice, due to (a) unripe fruit, (b) over ripe fruit, (c) 
watering normal apple juice, (d) second pressing of water-treated 
pomace, (e) the use of fruit normally poor in sugar. (2) Condi- 
tions unfavorable to the necessary fermentation processes, such 
as (a) dirty fruit, (b) unclean barrels, (c) too low tempera- 
ture, (d) lack of air from filling barrel too full or stopping the 
bung-hole. (8) Lack of proper care after the vinegar is made, 
by leaving the cider standing at too high a temperature with the 
bung open and the barrels only partly filled. 
12. Directions for Home-Manufacture of Cider Vinegar.—(1) 
Kind of apples to use. Only clean, sound, ripe apples, giving a 
juice containing not less than 8.5 per ct. of sugar should be 
used. (2) Preparation of apple juice. Cleanliness should be 
observed in grinding and pressing. Avoid. the use of juice made 
from second pressing of pomace. (3) Putting apple juice in 
barrels. The barrels should be carefully cleaned and thoroughly 
treated with live steam or boiling water and should be filled about 
two-thirds or three-fourths full of apple juice. The bung should 
be loosely placed in the hole or preferably the hole loosely plugged 
with a stopper of absorbent cotton. (4) Management of alcoholic 
fermentation. The barrels of apple juice should be kept at a 
temperature of 65° F. to 70° F., if fairly rapid fermentation 
