Aug. 1, 1924 
Freezing Injury of Apples 
125 
two, and the procedure of the experi¬ 
ment was similar to that of those 
already described, with subsequent 
storage at 32° for two and one-half 
weeks for Winesap and Yellow Newtown 
(Table XIX). 
Table XIX.— Internal temperatures of 
certain Winesap } Yellow Newtown , 
Rhode Island Greening , Ben Davis , 
and Rome Beauty apples while ex¬ 
posed to temperatures between 25° F. 
and 26° for different lengths time a 
Apple No. 
Internal temperatures of the 
fruit and length of period 
24-hour 
period 
48-hour 
period 
72-hour 
period 
WINESAP 
° F. 
o ^ 
o jp 
1.. 
27.0 
28.0 
27.5 
2„__'.. 
26.5 
27.5 
27.0 
3.. 
25.0 
26.5 
26.5 
YELLOW NEWTOWN 
1. 
27.0 
26.0 
28.5 
2...... 
28.5 
28.0 
27.5 
3. 
27.0 
26.5 
27.5 
RHODE 
ISLAND GREENING 
1_ 
29.0 
27.5 
27.0 
2. 
26.5 
28.0 
27.0 
BEN DAVIS 
1. 
29.0 
27.0 
27.0 
2_ 
29.0 
27.0 
27.0 
ROME BEAUTY 
1. 
27.5 
28.5 
28.0 
2__ 
27.0 
29.0 
27.5 
“Average freezing points of the varieties used 
were: Winesap, 28°; Yellow Newtown, 28.8°; Rhode 
Island Greening, 28.8°; Ben Davis, 28.9°; Rome 
Beauty, 29°. 
The temperatures indicated that ice 
formation had taken place in many 
apples at the 24-hour period; and the 
hard-frozen condition of the fruit at the 
48-hour period showed that it had 
proceeded to a considerable extent in 
all of the fruit. A drop in the apple 
temperatures would indicate that the 
major portion of the ice possible in the 
tissue at that temperature had formed, 
and that the fruit was losing heat more 
rapidly to the environment than it was 
gaining from the heat of fusion as new 
amounts of ice were formed. 
As has been observed in apples 
frozen at temperatures considerably 
below and just below their freezing 
point, the fruit of the five varieties 
subjected to temperatures near 26° F. 
showed a progressive softening as the 
time of exposure increased. In some 
varieties this is more noticeable than 
in others, due not to varietal peculiari¬ 
ties alone, but also to such conditions as 
differences in the size of the apples, the 
water content of the fruit, and their 
effect on the degree of ice formation. 
Table XX.— Effect of freezing apples 
at temperatures between 25° F. and 
26° upon softening as measured by 
pressure tester 
Period of ex¬ 
posure to 
freezing 
temperatures 
Period and temper¬ 
ature of 
subsequent 
storage 
Pressure in 
pounds 
necessary 
for puncture 
Pared 
Unpared 
WINESAP 
None- _ 
None _ . _ 
13.5 
16.7 
Do_ 
24 hours at 70° F__ 
13.0 
17.2 
24 hours. 
.....do.... 
12.6 
15.8 
48 hours_ 
_do.... 
12.6 
16.3 
72 hours. 
.do... 
11.9 
15.2 
None_ 
234 weeks at 32.... 
.do__ 
12.7 
16.2 
24 hours. 
12.1 
16.3 
48 hours_ 
_do... 
12.4 
15.4 
72 hours.. 
.do__ 
12.4 
14.8 
YELLOW NEWTOWN 
None_ 
None.... 
14.3 
21.7 
Do.—’ 
24 hours at 70°_ 
14.1 
21.4 
24 hours_ 
_do__ 
12.9 
20.5 
48 hours_ 
_do_ 
12.9 
19.9 
72 hours. 
_do.. 
11.4 
18.6 
None__ 
2}4 weeks at 32° _ 
_do... 
13.7 
20.6 
24 hours. 
13.8 
19.8 
48 hours.. 
.do.. 
12.5 
19.0 
72 hours. 
_do... 
12.0 
18.7 
RHODE ISLAND GREENING 
None__ 
None_ 
11.7 
13.9 
Do.. 
24 hours at 70°_ 
11.7 
13.8 
24 hours_ 
._ ..do.... 
10.0 
12.6 
48 hours 
_do _ 
9.6 
12.0 
72 hours.. 
_do. 
9.0 
11.4 
BEN DAVIS 
None.- _ 
None_ 
15.1 
19.9 
Do. 
24 hours at 70°- 
15.0 
18.8 
24 hours.. _ _ 
_do__ 
13.9 
18.5 
48 hours. 
_do. 
13.1 
17.6 
72 hours_ 
_do... 
13.3 
17.6 
ROME BEAUTY 
None. .. 
None.... 
12.4 
15.9 
Do.. 
24 hours at 70°- 
11.1 
15.4 
24 hours. 
_do.. 
11.4 
14.8 
48 hours_ 
.do-- 
11.7 
15.6 
72 hours . . 
.do... 
10.9 
14.5 
The acidity changes are not given in 
table form, since they were not signifi¬ 
cantly different and resemble those for 
earlier freezing tests. The majority of 
cases exhibited no visual injury what¬ 
ever, though a few showed a slight trace. 
SUMMARY AND CONCLUSIONS 
1. Freezing-point temperatures of a 
considerable number of important com¬ 
mercial varieties of apples have been 
determined. The average freezing point 
of all the varieties, both eastern and 
western grown, was 28.5° F., the 
maximum 29.4°, the minimum 27.8°. 
