Dilley and Dewey (12) found that fruit in 20-bushel bulk boxes could be 
successfully dunked in a tank containing DPA at a concentration of 2,000 p.p.m., 
using a modified forklift truck, Use of the spreader-sticker "'Plyac'' with DPA 
eliminated DPA injury, sometimes encountered in treating Red Rome apples. 
In Massachusetts, Southwick (117) found that neither preharvest sprays 
nor postharvest dips with DPA or with Stop-Scald gave good scald control on 
McIntosh or Rome Beauty apples in regular cold storage, The best approach to 
scald control with these varieties in Massachusetts appeared to be CA storage. 
Martin (50) reported a steam tunnel application procedure, whereby fruit 
is coated with DPA from the steam of a boiling DPA solution. After a brief 
treatment, the water evaporates leaving a fine deposit of DPA. Denmead, Vere- 
Jones, and Atkinson (11) in New Zealand described an oil-water emulsion treat- 
ment with DPA using Octaro oil. The fruit is first wet with water, then drained, 
then drenched with the emulsion for 1 to 10 minutes to get the needed uptake for 
the variety, then drained for 30 seconds before rinsing with water. Padfield 
and Clark (73) found this procedure satisfactory for controlling scald on Deli- 
cious, Dougherty, and Rome Beauty varieties. An uptake of less than 5 micrograms 
of DPA per square centimeter provided scald control, Hardenburg and Anderson 
(37) and Mattus (55) found that applying Stop-Scald or DPA with a drip applicator 
using a revolving brush gave nearly as good scald control as a dip treatment. 
This method is the same as that used for waxing some types of produce. It is a 
very economical method of applying scald inhibitors, 
Pierson and Schomer (83) washed apples 1 to 4 weeks after a DPA dip. With 
Delicious apples, if they were washed in less than 3 weeks, the maximum benefit 
from DPA was not obtained, Winesap could be washed 2 weeks after being dipped 
in DPA and still have excellent scald control. 
DPA wraps and DPA treated oiled wraps provided good scald control in 
numerous tests and were much superior to conventional oiled wraps (10, 23, 34, 
35, 3/7, 52, 55, 96, 109, 122, 123). The most acceptable quantity of DPA was 
1.5 mg. per sheet. Ginsburg (24) had good results with wraps containing 0.7 mg. 
per sheet on South African varieties. Of the two types of DPA wraps, DPA treated 
oiled wraps were superior to plain DPA wraps (37, 109). 
Raphael and O'Loughlin (86) packed Granny Smith apples in corrugated cell 
cartons which had been treated with Stop-Scald and obtained effective scald con- 
trol. 
Mattus (54, 55) and Hardenburg and Anderson (37) noted that good coverage 
with Stop-Scald was necessary for scald control, Since Stop-Scald fluoresces 
under ultraviolet light in the dark, it is relatively easy to check the fruit 
coating with various application methods. Coverage was poorer on early picked 
fruit than on fruit picked later. Good coverage was obtained easily on Stayman 
and Winesap varieties, but coverage was poorer on Delicious, Jonathan, and Grimes 
Golden varieties. Coverage was improved by lengthening the time of treatment, 
increasing the emulsion concentration, or raising the emulsion temperature to 
100° or 120° F. The latter was particularly effective as a method of improving 
coverage with scald inhibitors. Padfield, Atkinson, and Clark (72) also found 
that warming Stop-Scald treating emulsions to 100 to 110° F. increased the up- 
take of the inhibitor. However, for New Zealand varieties warming the treating 
liquid was unnecessary for satisfactory scald control. Coverage also was better 
on warm (70°) than on cool (40°) fruit (37, 54). Daines (10) found that Stop- 
Scald used on Stayman was very effective when apples were warm, but its effi- 
ciency was sharply reduced when apples were cold (32°) when treated. 
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