during April and May, the warmest part of the apple shipping season. During 

 transportation southward the apples had a tendency to become soft from pro- 

 gressively warmer temperatures unless adequate refrigeration was maintained. 



In the three experimental shipping tests of controlled-atmosphere apples, 

 the load patterns were revised so all the boxes in succeeding stacks of the 

 loads were in the identical positions as those in the first stack. Thus air- 

 channels were provided from the front to the rear of the load along each side- 

 wall of the trailer. This, coupled with the allowance of a space of 10 to 12 

 inches between the rear of the load and the rear doors of the trailer, greatly 

 increased the circulation of air, thereby facilitating more effective refriger- 

 ation during transit. Where the revised loading pattern was used, the maximum 

 fruit temperature at destination was held to 40° to 42 F. compared with 

 temperatures as high as 50° to 60 along the sidewalls in loads not having the 

 air channels . Although this loading pattern seems to afford favorable results, 

 more experimental tests with it are needed before definite conclusions on its 

 effectiveness can be reached. 



The tests also showed that the circulation of air in the trailer body is 

 enhanced if strips are provided along the sidewalls and rear doors to keep 

 the load from fitting too tightly against them, by having larger grooves in 

 the floor channels, by using floor racks, by keeping the grooved floor channels 

 free of trash and dirt especially at the front bunker area, and by inserting 

 air vents in the apple boxes. 



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