STORAGE OF FRUITS, VEGETABLES, AND FLORISTS' STOCKS 13 



decay so largely responsible for their deterioration — that is, it is 

 impossible in the present state of knowledge to obtain fruits and 

 vegetables that have not been refrigerated but still have not changed 

 in any way since harvest, for comparison with similar lots that have 

 been in cold storage and are eventually removed. However, so far 

 as is now known, it is correct to say that for many fruits and vege- 

 tables cold storage at or near 32° F. is beneficial. Important excep- 

 tions are bananas, sweetpotatoes, tomatoes, cucumbers, melons, and 

 certain other horticultural products mentioned herein, the behavior of 

 all of which in storage is discussed later under appropriate headings. 



Sweating 



When fruits or vegetables are removed from a low temperature to 

 a higher one there is frequently a condensation of moisture from the 

 air on the cool surface of the commodity. This is known as sweating 

 and is more marked the higher the relative humidity of the outside 

 air. It should be prevented whenever possible in the case of onions 

 and the more tender fruits, because it favors the development of decay. 

 This does not mean that when any of these products sweat after 

 removal from an iced refrigerator car or a refrigerated room they 

 are sure to decay; it does mean that they are more likely to decay 

 than if they were dry after being unloaded and remained dry until 

 consumed. In this connection dryness means merely the absence of 

 liquid water on the surface. 



Sweating can be prevented to some extent, as in the British prac- 

 tice with eggs and certain other commodities, by allowing the fruits 

 or vegetables to warm up gradually. Under commercial conditions in 

 the United States this is rarely practicable, however, and the best thing 

 to do in very damp weather is to realize the risk, handle the product 

 carefully, and get it into consumption without undue delay. 



WAXING 



The application of waxing preparations to certain perishable prod- 

 ucts has been practiced commercially for several years. It probably 

 started with the waxing of citrus fruits and was followed by the wax- 

 ing of rutabagas. Its value for both of these products lies in the fact 

 that it not only improves their appearance but also prevents shrinkage 

 by restricting the loss of water. 



Waxing has been tried on a number of other products. In the case 

 of cucumbers and carrots it gives considerable promise and may 

 come into general use. It has been tried on cantaloups but did not 

 prove to be beneficial. 



(See 75.) 



CHOICE OF STORAGE CONDITIONS 



The storage conditions recommended herein for certain commodi- 

 ties represent either a compromise between two undesirable extremes 

 of temperature or humidity or a choice of the least harmful of two 

 such extremes. Grapefruit, for example, suffers less from decay at 

 low humidities than at high ; on the other hand, at low' humidities 

 it is subject to a pitting which, in fruit from regions where stem- 



