16 



CIRCULAR 2 78, U. S. DEPARTMENT OF AGRICULTURE 



Apples should not be handled while frozen, if such handling can 

 possibly be avoided. Water core does not develop or spread in storage, 

 and in varieties such as Yellow Newtown and Winesap it may actually 

 disappear after a few months' storage, especially if originally present 

 only in mild form. When large portions of the flesh are affected, 

 especially in soft-textured varieties like Jonathan, Delicious, Stayman 

 Winesap, and Rome Beauty, there is danger of subsequent break-down 

 and prompt disposal of the fruit is advisable. The diseases of apples 

 in storage are discussed in Farmers' Bulletin 1160 (8) and Miscel- 

 laneous Publication 168 (84) . 



For the storage of most varieties of apples the best results are 

 obtained by maintaining a temperature of 30° to 32° F. and a relative 

 humidity of 85 to 88 percent. However, as the storage temperature 

 approaches the freezing point of the fruit the hazard of freezing 

 increases unless the temperature is well controlled and there is good 

 air circulation. Yellow Newtown apples from the Pajaro Valley, 

 Calif., and Mcintosh and Rhode Island Greening apples from New 

 York should be held at 35° to 38° rather than at 32° to prevent the 

 development of internal browning or brown core. Grimes Golden 

 apples should be held at 34° to 36° instead of at lower temperatures 

 (71) in order to avoid soggy break-down. It should be remembered, 

 however, that at these higher temperatures the fruit cannot be held 

 as long as when stored at 30° to 32°, because of the possible develop- 

 ment of Jonathan spot and internal break-down. 



(See 9, 21, 36, 43, 71, 72, 73, 74-) 



If air-cooled storage is used, the temperature obtainable will usually 

 not be much lower than the average of the prevailing outside tempera- 

 tures. The nearer this is to 32° F. the better. 



The length of time apples can be held successfully in cold storage 

 will vary with the variety and with the district where grown, as well 

 as with their condition when harvested. Table 4 shows the normal or 

 average storage period and the maximum storage period for the more 

 important apple varieties when picked at proper maturity and stored 

 immediately at 30° to 32° F. 



Table 4. — Nonnal and maximum storage periods for important apple 



varieties 



Variety 



Jonathan 



Grimes Golden 



Mcintosh 



Golden Delicious 



Cortland 



Rhode Island Green- 

 ing 



Stayman Winesap 



York Imperial 



Storag 



b period 



Nor- 

 mal 



Maxi- 

 mum 



Months 

 2 to 3 

 2 to 3 



2 to 3 



3 to 4 

 3 to 4 



Months 

 4 

 4 

 4 to 5 

 5 

 5 



3 to 4 



4 to 5 

 4 to 5 



6 

 5 to 6 

 5 to 6 



Variety 



Arkansas (Black 



Twig) 



Delicious 



Northern Spy 



Baldwin 



Rome Beauty 



Ben Davis 



Winesap 



Yellow Newtown 



Storage period 



Nor- 

 mal 



Months 



Maxi- 

 mum 



Months 



6 to 

 6 to 



