New YorK AGRICULTURAL EXPERIMENT STATION. 157 
TABLE XIV.—VARIATIONS IN COMPOSITION OF VINEGAR UNDER 
UNIFORM CONDITIONS. 
Borrue. Anevnen epenine Solids. Acetic acid. | Fixed acid. 
Per ct. Per ct Per ct 
Ugieyenietes Gees ocic. cc) 2 O Yeans.....8 1.0139 1.70 ; 5 
18 305 oid Gan Hee eae DPYearses le 1.0122 1.58 5.44 0.00 
Crete cle se susfaye ais 5 ays, 5 years.....« 1.0095 1.70 2.10 0.00 
(6 lhe Rice CHEE Ren 5) Vearss sc ous 1.0029 0.60 | alkaline.... 0.00 
In bottles a and b, the differences are only what might ordi- 
narily be expected, but in c the acetic acid has dropped to only 
about 2 per ct. while in d the solids had been! greatly reduced and 
the acetic acid had entirely disappeared, and not that alone, but 
the liquid was actually alkaline. The liquid in ec was very dark 
colored and the “mother” black, showing evidence of acetic 
destroying ferment. These differences are readily explained as 
being due to the activity of different ferments in the different 
bottles, but in the absence of special study of the organisms, we 
are unable to say what specific organisms were present. It is 
probable that the stopper in bottle d was so loosely inserted as to 
admit air freely. 
THE BEHAVIOR OF THE MALIC ACID OF APPLE JUICE 
DURING THE FERMENTATION PROCESSES. 
Malic acid in the form of free acid or acid salts in the juice of 
different varieties of apples varies greatly in amount. In the 
analyses published in Table II, it averages a little over 0.5 per 
et. varying all the way from 0.1 per ct. in the Sweet Bough to 
1.15 per ct. in the Red Astrachan. In the juice of the different 
varieties used in our experiments the malic acid varied from 0.41 
to 0.66 per ct., averaging 0.53 per ct. A special examination 
of the juice of several varieties of apples showed practically no 
neutral salts of malic acid. Early in our work we noticed that 
the amount of malic acid decreased when the apple juice was 
allowed to ferment, and the diminution continued until the 
malic acid nearly disappeared. The work of Browne*® shows 
similar results. In the following table we present our results in 
> detail: 
sAnnual Report of the Pennsylvania Department of Agriculture, 1901, f 
pp. 128-9. 
