Scald Control 
The standard method of control has been to avoid picking too early and to 
use mineral-oil-impregnated wraps or shredded paper when storing scald-suscepti- 
ble varieties. Oiled wraps, used commercially on many varieties since 1920, 
usually reduced scald but have not always provided adequate control. In Russia, 
apples are sometimes packed in wood shavings to retard scald (59). It is hoped 
that commercial use of the new chemical scald control treatments, described 
later, will greatly reduce losses in the future. 
Oils and Waxes 
Certain oils and waxes have reduced scald in controlled experiments but 
they are not used commercially. Shutak and Christopher (97, 98) found that 
treating apples before storage with a 3-percent mineral-oil emulsion controlled 
scald on Cortland apples. A 5-percent mineral-oil orchard spray prior to harvest 
reduced scald but caused some leaf injury. Smock and Southwick (112) reported 
that results were inconsistent when apples were coated with mineral oil. In some 
years it gave no scald control. They reported that a wax designated as 489AM 
significantly reduced scald on Rhode Island Greening apples. Hall, Sykes, and 
Trout (30, 31, 32) studied extensively the coating of apples with oils. An al- 
cohol solution of 8 to 10 percent castor oil and shellac used as a coating re- 
duced scald, but was less effective than good oiled wraps. They reported that 
oil coatings reduced scald more than controlled-atmosphere storage. 
Oiled Paper 
Oiled paper containing 15 to 20 percent of its finished weight in mineral 
oil, used as individual wraps or at the rate of three-fourths pound of shredded 
paper per bushel, has been a standard scald control measure for many years. Al- 
though oiled paper is often effective, its use has declined because of costs of 
applying the wraps and new handling methods. Many reports issued since 1945 
still show the effectiveness of oiled wraps (4, 14, 15, 23, 27, 37, 41, 46, 65, 
66, 68, 69, 77, 86, 89,.112,.113, 133,135)... Fidler: (14) showed, that oited 
wraps provided better scald control than air purification filters in the storage 
room. Smock and Southwick (113) found that air purification plus the use of 
oiled wrappers provided better scald control than either used alone. Whittaker 
(135) in Australia showed that the scald susceptible variety Granny Smith should 
not be stored more than 2 months without the protection of oiled wraps. Padfield 
(69) found that rewrapping apples with fresh oiled wraps after 3 months' storage 
did not improve scald control, Hall (27) pointed out that the oil content of 
wraps may decrease markedly during storage from one season to the next. The 
loss can be minimized by keeping oil wraps well protected with waxed paper or 
polyethylene film. 
Air Purification and Ventilation 
Many attempts have been made to remove volatiles from apple storages, 
assuming that they may be causing scald. Activated carbon or brominated acti- 
vated carbon filters reduced scald in several studies (14, 20, 21, 104, 105, 
113, 132). In other-studies, air purification did not appreciably reduce scald 
198 
