526 
Journal of Agricultural Research 
Vol. XXVI, No. n 
RETENTION of oil by the wrappers 
A study was made of the extent to which the various oiled wrappers 
gave up their oil to the apples or to other objects with which they came 
in contact. Oil determinations were made on fresh unused wrappers, on 
similar wrappers after removal from apples at the end of the storage 
period, and on the box-liners from the same packages. Tests were also 
made on the freedom with which the various wrappers gave up their oil 
to sheets of blotting paper, the oil content of fresh wrappers being com¬ 
pared with that of similar wrappers thfit had been held between sheets of 
blotting paper under io pounds pressure for 48 hours. The oil determina¬ 
tions were made by petroleum ether extraction with the Soxhlet appa¬ 
ratus. The preliminary work was done by the writers and the results 
checked up and confirmed by determinations made by Dr. G. S. Jamieson 
and Mr. W. F. Baughman of the oil, fat, and wax laboratory, Bureau of 
Chemistry. All percentages are computed on the dry weight of the oiled 
paper. The results are reported in Table III. 
Table III .—Dosage of oil in the wrapper: retention of oil 
Dosage of oil 
Wrappers. on fresh 
wrappers. 
Dosage of oil 
after use on 
the apples. 
Gm. of oil per 
wrapper. 
Dosage of oil 
after 48 hours 
between blot¬ 
ters. Gm. of oil 
per wrapper. 
! 
I Dosage of oil 
in box liners 
1 after use in 
] contact with 
j oiled wrap- 
i pers. 
Number. 
Weight of 
paper. 
! 
Size, i 
IO X IO 
IO X IO 
10 x 10 
IO X IO 
IO X IO 
Per 
cent. 
Gm. 
per 
wrap¬ 
per. 
Re ed in ' 
Retain¬ 
ed. 
Lost. 
©• 3477 
.3718 
. 3669 
. 2566 
. 2050 
Per 
j cent. 
Gm. 
per 
box. 
i 
3a. 
14-lb. 
21.3 
24.4 
26. 3 
14. 2 
16. 7 
0.4097 
.4481 ! 
•4356 1 
•3191 | 
• 2528 
O. 3436 O. 0661 
i . 3875 : • 0606 
i . 3638 .0718 
l .2640 .0551 
. 2080 .0448 
0. 0620 
■ 0763 
.0687 
• 0625 
• 0478 
! 9 - 6 
13-6 
7 - 7 
4 - 9 
IO. I 
40512 
! 5.2820 
: 2.7893 
2.1016 
7 - 575 © 
II.. . .. 
14-lb........ 
na. 
12-lb. 
12. . 
14-lb. . .. 
13a. 
12-lb. 
Average. 
• 3731 : - 3 L 34 .0597 
• 0635 
• 3096 
1 
4 - 3598 
The data reported in Table III show some contrast in the freedom with 
which the different wrappers gave up their oil during storage and a still 
greater contrast in the freedom with which they released their oil to dry 
blotters. A comparison of these data with that reported in Table II, 
however, gives little evidence of correlation between the freedom with 
which the wrappers released their oil and their efficiency in scald control. 
The average loss of oil by the wrappers during storage was approximately 
0.0597 g m * P er wrapper. The amount taken up by the liners varied 
widely but averaged 4.3598 gm. per box. With a box containing 113 
apples this would mean that the liner had taken an average of 0.0386 
gm. of oil from each wrapper, leaving 0.0211 gm. of the above loss to 
be accounted for by passage to the apples, to the box, and to other objects. 
In order to obtain further evidence in regard to the action of the oil, 
apples were wrapped in one or more unoiled wrappers and oiled wrappers 
applied outside of these. The fruit was thus largely protected from the 
oil, yet kept in close proximity to it. The resulting scald control is shown 
in Table IV. 
The average degree of scald reported in Table IV for the apples that 
were unwrapped or in unoiled wrappers is 39 per cent, and the average 
for the apples in oiled wrappers 2.7 per cent, while the average where 
one unoiled wrapper was used inside of an oiled one is 4.9 per cent, and 
