COLD STORAGE FOR APPLES AND PEARS 7 



Fumigating the storage rooms is another method of killing molds 

 and one that will reach areas not accessible to sprays. Sulfur dioxide 

 is commonly used for this purpose. It is produced by burning sulfur 

 at the rate of 5 pounds per 10,000 cubic feet of space. As soon as the 

 sulfur has been ignited, the rooms should be closed for 24 hours. 

 Sulfur furnaces should not be placed near motors or delicate 

 machinery, as the fumes are corrosive and prolonged heavy concen- 

 trations are destructive to machinery parts. Removal of such equip- 

 ment or protection by covering is a recommended precaution. 



In burning sulfur, precautions against fire should be taken by 

 placing the furnace over a 3-inch layer of sand or in a receptacle of 

 water with a surface of 2 feet greater radius than the furnace. 



Sulfur dioxide is injurious to apples and pears, and no fruit should 

 be placed in the rooms until all traces of gas have disappeared. It is 

 likewise a strong irritant to eyes and mucous membranes, and care must 

 be exercised to avoid contact with the fumes during and after fumi- 

 gation. Doors should be opened to air the rooms thoroughly after 

 fumigation and before they are entered by workmen. For this reason 

 it is feasible to fumigate only during the season when the storage space 

 is not in use. 



STORAGE BEHAVIOR OF APPLES AND PEARS 



Success in the storage of apples and pears is dependent upon giving 

 due consideration to their inherent characteristics and to their nor- 

 mal cold-storage life, as well as to the handling of the fruit before 

 storage (8,20). 



Apples 



A temperature of 30° to 32° F. and a relative humidity of 85 to 88 

 percent give best results in the storage of most varieties of apples in 

 most parts of the United States. Certain varieties, however, some- 

 times will not tolerate continuous low-temperature storage. Yellow 

 Newtown apples from the Pajaro Valley of California and Mcintosh 

 and Rhode Island Greening apples from New York and New England 

 should be held at 35° to 38° to prevent the development of internal 

 browning and brown core. Grimes Golden should be held at 34° to 

 36° to prevent soggy break-down. Under conditions described below, 

 certain other varieties should be stored at temperatures higher than 

 32° to avoid storage disorders. 



The higher the storage temperature the faster the apples will ripen 

 and the sooner the end of their storage period will be reached. Apples 

 stored close to the place where they are to be consumed may be held 

 until they are ripe, and if in the hands of the consumer the day fol- 

 lowing removal from storage they will still be acceptable. Apples 

 stored at more distant points must have sufficient life left when with- 

 drawn from storage to withstand the higher temperatures of trans- 

 portation and distribution. The longer apples are stored the shorter 

 their life after removal to higher temperatures. Thus, apples that 

 leave cold storage in apparently good condition may reach the con- 

 sumer in an overripe and mealy condition with many decayed fruits 

 when distribution requires 10 days to 2 weeks. Some forms of deteri- 

 oration of apples in storage are discussed here. 



