COMMERCIAL STORAGE OF FRUITS AND VEGETABLES 19 



house, the packages of fruit are usually stacked closely together to 

 prevent excessive drying out. Dried fruits do not need the ventila- 

 tion required by fresh, living fruits and vegetables. The storage 

 room should not be in a basement because of the danger of too high 

 humidity and the consequent development of mold ; in fact, an upper 

 floor is preferable, as such a location is usually drier. The storage 

 room should be kept dark and should be well screened to prevent the 

 entrance of insects or rodents. 



In cold storage, temperature and humidity conditions are more 

 easily controlled, and vermin are usually held in check or kept out 

 entirely by the low temperature. Dried fruits will usually keep for 

 about a year in cold storage (at 32° F.), whereas in the warehouse 

 or in common storage 4 to 6 months is often the extreme limit. After 

 prolonged storage, even at low temperatures, dried apples darken, 

 and prunes, figs, and raisins tend to " sugar ", especially, if their 

 moisture content is high when they are first stored. 



FROZEN FRUITS 

 (Temperature, 15° to 20° F.) 



Frozen fruits, packed either with or without sugar, should be held 

 in tightly closed containers and preferably at about 15° F. if they 

 are to be stored for several months. The temperature of the fruit 

 should not rise above 20° during the storage period, otherwise there 

 is danger of fermentation and spoilage. The same undesirable 

 changes may occur if the freezing takes place too slowly. Exper- 

 ience has shown, however, that they can usually be prevented if the 

 fruit is sound and clean when packed and the temperature of the 

 freezing room is kept below 10° F. Some packers use a temperature 

 as low as —5° (6). 



NUTS 

 (Temperature, 30° to 32° F. ; relative humidity, 75 to 80 percent) 



The commercial nut crop, including walnuts, filberts, almonds, 

 Brazil nuts, pecans, and peanuts, is usually held in ordinary ware- 

 house storage through the winter following harvest. If any of it is 

 to be kept through the following summer, either as nut meats or in 

 the shell, it should be placed in cold storage in March or early April 

 at a temperature of about 32° F. Some handlers of pecans prefer to 

 put them into cold storage as early as February. The relative 

 humidity for nuts should be maintained at 75 to 80 percent. 



The commercial crop of chestnuts is rarely held in any other way 

 than in cold storage, whereas peanuts are held almost entirely in com- 

 mon or warehouse storage. Brazil nuts can usually be kept satis- 

 factorily in warehouse storage, provided they are well dried or cured 

 before being stored. If it becomes necessary or desirable to hold 

 them through the next summer, they should be placed in cold storage. 



Nuts that are sound and well cured when stored, and are trans- 

 ferred to cold storage at the proper time, as indicated above, should 

 remain free of mold or rancidity for about a year after harvest. 



The fumes of ammonia are very objectionable in rooms where nuts 

 are stored, because they produce a browning or blackening of both 

 shells and meats. 



