FACTORS INFLUENCING KEEPING QUALITY. 21 



of the fruit-storage business and its relation to the fruit-growing indus- 

 try are emphasized as the apple business enlarges. 



INFLUENCE OF STORAGE TEMPERATURE. 



The investigations indicate that the ripening processes are delayed 

 more in a temperature of 31° to 32° F. than in 35° to 36° F. The 

 apple keeps longer in the lower temperature, it scalds less, the fruit 

 rots and molds are retarded to a greater extent, while the quality, 

 aroma, flavor, and other characteristics of the fruit are fully as good, 

 and when removed from storage it remains in good condition for a 

 longer period. 



The impression is quite general that fall varieties and the tender 

 early winter sorts, like Fameuse, Wealthy, and Grimes, are injured in 

 some way by the low temperature, but the investigations of the 

 Department of Agriculture indicate that these varieties behave more 

 satisfactorily in every respect when stored at 31° to 32° F. 



If the fruit is intended for storage for a short time only, and it is 

 desired to have it ripen before removing it from the storage house, 

 then a higher temperature may be desirable to hasten the maturity. 



The influence of the temperature on the ripening processes appears 

 to depend on the condition of the fruit. Baldwin, Esopus Spitzen- 

 &wn/, Roxbury, Jonathan, Lady Sweet, and other long- keeping eastern- 

 grown varieties have been held in prime commercial condition through- 

 out the storage season in a temperature of 35° F. when carefully 

 picked and handled and stored soon after picking; but when the fruit 

 was carelessly handled or the storage was delayed in hot weather, then 

 a temperature of 31° to 32° F. was required to retard the ripening. 



It might be safe to use a temperature of 34° to 35° F. in a storage 

 house located near the orchard, in which the fruit may be stored imme- 

 diately after harvesting, but for general commercial apple handling, 

 a temperature as low as 32° F. is needed to overcome the abuses that 

 usually arise in picking, packing, and shipping. 



No definite investigations have been made by the Department of 

 Agriculture as to the effect of temperatures lower than 31° F. The 

 exact freezing point of apples has not been determined, but it is below 

 this point. It may possibly vary with the composition or condition 

 of the variet}^. Under the most favorable conditions, apples are some- 

 times commercially stored at 30° F. without injury, but 31° F. should 

 be considered a critical temperature below which it is unsafe to store 

 this fruit, except in houses that are properly constructed and in which 

 the temperature is maintained uniform in all parts of the rooms. 



Apples are sometimes frozen in the storage rooms owing to a con- 

 siderable drop in the temperature or to a poor distribution of the cold 

 air. If the fruit compartment adjoins a freezer room and the insulation 

 is poor, the fruit may be frozen in packages piled close to the freezer 



