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CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE 



of the fruit approached that of the air in the storage room. The insulat- 

 ing effect of the liners, pads, and shredded oiled paper ordinarily used 

 is brought out in these results as well as in those in table 1. The effect 

 of air movement in increasing the rate of cooling is also brought out 

 clearly. When the rate of air movement was about 200 feet per minute, 

 the apples without packing material cooled to 32° in 36 hours, while 

 in still air they required more than 96 hours to reach this temperature. 

 In the baskets with liners, pads, and shredded oiled paper similarly 

 packed apples required 57 hours in the air moving at 200 feet a minute 

 and more than 156 hours in still air. 



In stacking packages in storage, adequate provision for the cold air 

 to reach all packages in the room is essential, not only for the rapid re- 

 moval of field heat but also for the continuous removal of the heat of 

 respiration, thereby preventing the accumulation of heat and develop- 

 ment of warm pockets in the storage room. This is not so serious a 

 problem when apples are packed in bushel baskets (fig. 5) as when they 

 are packed in crates, boxes, and cartons. Crates, boxes, and cartons 

 should be spaced with from 2 to 3 inches between rows of stacks, and the 

 rows should run in the direction of the air currents across the room. 

 It is especially important to provide spacing when tight, close-fitting 

 packages like cartons are stored; lath or other dunnage strips should be 

 used to separate the packages in each stack. 



Figure 5. — Method of stacking bushel baskets of apples and staggering them by 

 placing each basket on the edges of those beneath to keep pressure away from cen- 

 ters of lids. Stacking baskets this way, instead of putting alternate baskets upside 

 down as is sometimes done, permits better air circulation. Workmen should never 

 stand or walk on the baskets. 



