3io 
Journal of Agricultural Research 
Vol. XI, No. 7 
In the interpretation of the above contrasts in color development it 
becomes of interest to know whether the depressing effect of the moist 
chambers was due to the high humidity or the poor aeration. Some 
further experiments carried out at 15 0 throw light upon this subject. 
Fig. ai.—Graphs showing the influence 
of aeration and humidity upon the 
color development of Grimes apples 
in storage at 15 0 C. The perpen¬ 
dicular indicates the percentage of 
color, the base line the number of 
As has already been stated, two boxes were 
maintained at this temperature, one in which 
the relative humidity ranged from 65 to 75 
per cent but usually stood at 70 per cent, 
and another in which the relative humid¬ 
ity ranged from 85 to 95 per cent and usually 
stood slightly above 90 per cent. There 
was less fruit in the former box and the 
accumulation of carbon dioxid may there¬ 
fore have been slightly less in this case 
than in the more humid box. In figures 21, 
22, and 23 the color development in the open 
containers under these conditions is com¬ 
pared with that in moist chambers at the 
weeks of storage, and the curves give 
the comparative color development 
obtained with 70, 90, and 100 percent 
relative humidity, respectively. 
With the graph marked “Mioo 1 ' the 
apples were held in moist chambers, 
while with the others they were kept 
in open containers. The apples were 
of the same lot as described in the 
legend of figure 13. 
same temperature. In figures 22 and 23 
other curves are given showing the color 
development on apples in jars where the 
air was 
kept 
satu¬ 
rated, 
times a 
but was renewed several 
week. 
There was practically no contrast 
in color development between well- 
aerated apples exposed to a relative 
humidity of 70 per cent and similar 
apples exposed to a relative humidity 
of 90 per cent. It has already been 
pointed out that apples did not scald 
under either of these conditions. 
The color development in the moist 
chambers was much slower than in 
either of the above cases. The rel¬ 
ative humidity was 10 per cent 
higher in this case than in either of 
the former, and, as pointed out 
earlier in the paper, the aeration was very poor. Since increasing 
the relative humidity from 70 to 90 per cent has caused no checking in 
color development, it does not seem probable that increasing it from 
90 to 100 per cent would do so. In so far as this reasoning can be 
Fig. 22,—Graphs showing the influence of aeration 
and humidity upon the color development of 
Grimes apples in storage at 15 0 C. The perpen¬ 
dicular indicates the percentage of color, the base 
line the number of weeks of storage, and the 
curves give the comparative color development 
with 70, 90, and 100 per cent relative humidity, 
respectively. With the graph marked “Mico” 
the apples were held in moist chambers, with the 
one marked ‘ 'A100 ’ ’ they were in closed jars that 
had the air renewed six times a week, and in the 
other two cases they were kept in open contain¬ 
ers. The apples were of the same lot as described 
in the legend of figure n. 
