\Ua*l JLlA LdjA, oJ 'tLsx ' ^ 



ITED STATES DEPARTMENT OF AGRICULTURE 



DEPARTMENT BULLETIN No. 1133 



Washington, D. C. ▼ February 28, 1923 



THE FREEZING TEMPERATURES OF SOME FRUITS, 

 VEGETABLES, AND CUT FLOWERS. 



By R. C. Wright, Physiologist, and George F. Taylor, Associate Physicist, Office 

 of Horticultural and Pomological Investigations, Bureau of Plant Industry. 



CONTENTS. 



Page j Page. 



Introduction 1 ! Freezing points of cut Sowers 7 



Freezing points of fruits 3 | Recapitulation 7 



Freezing points of vegetables 5 | 



INTRODUCTION. 



There is an ever-increasing demand from those interested in the 

 growing, shipping, and handling of produce for exact data on the 

 freezing points, or the temperatures at which various products 

 freeze. 



The extent of damage due to the freezing of produce in transit 

 naturallv varies from year to year, but it is usually very heavy, 

 aggregating frequently several hundreds of thousands of dollars 

 during a year. This in general applies not only to such products as 

 apples and potatoes, most of which are grown in the North and har- 

 vested and shipped in the late fall and winter, but to products which 

 are grown in the South and Southwest during the winter and shipped 

 to the northern markets. This latter group includes citrus fruits, 

 strawberries, tomatoes, lettuce, string beans, cabbage, cauliflower, 

 eggplant, etc. Cars of these food products often leave the shipping 

 point under refrigeration and in 24 to 36 hours may pass into a zone 

 of freezing temperatures. As they approach the more northern 

 markets they may be exposed to temperatures ranging several degrees 

 below zero. Under some conditions when harvested in warm weather 

 some of these products may be precooled — that is, rapidly cooled to 

 a refrigerating temperature, either immediately before or directly after 

 they are placed in the car for shipment, in order to delay maturity 

 and consequent deterioration. Where precooling is practiced, it is, 

 of course, very important to know the temperatures to which the 

 product can be lowered with absolute safety. 



Note.— This bulletin gives the results of a portion of the work carried on under the projects "Factors 

 affecting the storage life of vegetables" and "Factors affecting the storage life of fruits." 



21854—23 



