thus advised when apples are picked after a rain, are handled immediately after 
removal from cold storage to room temperatures, or are handled after the wash- 
ing and packing operations (122). Some authors (68, 78, 79, 104, 119) estimate 
from 29 to 50 percent bruising takes place by the time raw-stock storage begins. 
Van Waes (104) thought pre-storage bruising of apples probably could be der 
creased to about 17 percent. 
Bruising in storage has been estimated to be about 34 percent (104, 119), 
with a reduction possible to about 16 percent. Shock recorders placed in boxes 
of apples have shown that when boxes of apples are handled individually, some 
apples nearly always receive serious impacts (77, 93). Pallets and forklift 
trucks thus are being adopted in many growing areas for the hauling and handling 
of apples to reduce bruising, and to save time in receiving, stacking, and han- 
dling at the packinghouse (28). As previously discussed, the use of similar 
equipment in the orchards was found to reduce bruising there also (93). 
Dumping apples onto the receiving belt has been considered to cause up 
to 96 percent of the packinghouse bruising, and it is believed this could be 
reduced between 68 and 80 percent (38, 114). Woodward (119) showed that care 
in dumping apples was more important than the type of container used for ship- 
ping the apples. 
Bruises caused by leaf eliminators have amounted to 82 percent for tra- 
verse roller-elevator methods, and 42 percent for level shuffle-board progres- 
sors (93). Tests by Burt (14) showed that McIntosh apples of 15-pound firmness 
run through a leaf eliminator bruised to the extent of only 1 percent. 
Smith and Wright (91) reported that different types of cleaning equipment 
was responsible for 45 times as much bruising in one packing plant as in another. 
In one instance, it was 15 times as great in one as in another, although the 
same type of equipment was used in each. They concluded this indicated sizable 
differences either in machine maintenance or operation, since the same quality 
of fruits was used in each of these plants. In 1949, they reported that apple 
bruising was 100 percent with a late-type dual-flood progressor, but was only 
11 percent when the apples were dry wiped with canvas covered rolls (93). They 
found 89 percent bruising by towel driers but only 37 percent when the apples 
were air dried. Short rag-wipers inflicted far less bruising than long washers. 
Also in 1949, Smith, Adams, and Wright (93) observed that bruising could 
be lessened by dumping apples into a water tank at the head of the receiving 
belt. By this method bruising was reduced from 121 to 49 bruises per 100 
fruits. A hand operated mechanical aid for dumping fruit was developed by 
Gaston and Levin in 1951 that allowed even unskilled operators to eliminate 
from 60 to 70 percent of the bruising at the receiving belt (38, 60). In 1960, 
Pflug and Dewey (81) noted that water submergence of bins during unloading 
caused only a fraction of the bruising that occurred in a tilting bulk-box 
dumper. When the bins were vertically submerged, the fruits acted as a unit 
and 80 percent of them remained submerged. Only the top 6 inches of apples 
arose above the water surface and then spread out to a single layer. 
Hunter, Kafer, and Meyer (53) compared bruising caused by a float-roll 
sorting table with that caused by a reverse-roll sorting table. They concluded 
that there was no difference in bruising on the two types of tables. The sort- 
ing operation is believed not to cause much increase in bruise damage (36). 
Washing and grading operations have been reported to be responsible for 
37 to 97 percent of all packinghouse bruises, second only to packing operations, 
with the potential reductions estimated between 4 and 55 percent (38, 91, 104). 
Roberts found that grading machines operated with care did not cause excessive 
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