Apr 14.1923 Internal Browning of the Yellow Newtown Apple 
169 
acidity decreased with maturity and subsequent storage, the active 
acidity as indicated by the Ph value of the expressed juice remained 
practically constant. This possibly accounts for the fact that the 
decrease in total acidity does not influence the resistance of the fruit to 
browning. 
Table I .—Relation of time of harvesting of the fruit to internal browning 
SEASON or 1919-20 
Storage temperature. 
Date of 
picking. 
Date of 
storage. 
Condition of fruit at end storage period, approxi* 
mately Apr. i. 
Normal. 
Trace, 
Slight, 
Moderate. 
Severe. 
•c. 
Per cent. 
Per cent. 
Per cent. 
Per cent. 
Per cent. 
Sept. 28 
Oct. 
2 
45 
50 
5 
0 
0 
Oct. 18 
22 
SO 
45 
5 
0 
0 
2.2... 
Nov. 22 
Dec, 
8 
45 
45 
10 
0 
0 
0. 
Sept. 28 
Oct. 
2 
40 
20 
IS 
IS 
10 
Oct. 18 
22 
20 
45 
20 
10 
5 
Nov. 22 
Dec. 
8 
15 
35 
20 
10 
20 
SEASON OE 1920-21 
2,2. 
Sept 27 
Sept. 
30 
IS- 
10 
5 
10 
0 
Oct. 16 
Oct. 
19 
60 
35 
5 
0 
0 
2.2... 
Nov. 6 
Nov. 
26 
5 
45 
30 
20 
0 
0. 
Sept 27 
Sept. 
30 
30 
40 
20 
10 
0 
Oct. 16 
Oct. 
19 
20 
45 
25 
10 
0 
Nov. 6 
Nov. 
26 
0 
30 
45 
25 
0 
Table II .—The relation of time of harvesting of the fruit to the rate of development of 
browning 
Storage temperature. 
*C. 
O 
O 
o. 
Date of 
picking. 
Condition of fruit. 
Weeks in 
storage. 
Market- 
able.» 
Unmarket¬ 
able. 
Sept. 26 
Hard green. 
20 
Per cent. 
60 
Per cent. 
40 
Oct. 16 
Firm green. 
15 
60 
40 
Nov. 6 
Overripe.. 
6 
60 
40 
' Marketable fruit includes both normal and trace browned specimens. 
l^FEECT OF TEMPERATUR]E UPON INTERNAL BROWNING 
STORAGE TEMPERATURE 
At the time apple storage was introduced in California, investigations 
by Powell and Fulton {13) had brought the cold-storage men to the 
general belief that all apples could be stored most successfully at — 5/9® 
to o® C. It was soon found, however, that great losses were incurred 
through the deterioration of Yellow Newtown apples of the Pajaro Valley 
at these temperatures. As a result of these losses investigations (16) 
were undertaken which brought about the storage of all the Pajaro Valley 
apples at 2.2®. 
30616 — 23 — 
