COLD STORAGE /OF V EGtJTAEI^S , i o I 



merely one method of taking advantage of the retarding effect of 

 cold on the action of such organisms. 



Precooling. Another important use of artificial cold which will 

 aid producers to deliver highly perishable products to distant mar- 

 kets in a satisfactory condition is precooling. Precooling can be 

 accomplished in a measure by natural means and a little extra care. 



Precooling reduces the temperature of perishable products to a 

 point below which putrefactive organisms do not work rapidly. By 

 lowering the temperature before shipping the product, less work is 

 thrown upon the refrigerating equipment of the car. The proc- 

 esses of ripening and decay are quickly checked and do not be- 

 come active so long as the temperature of the car remains below 

 the danger point. 



The difficulty with the present system of loading directly from 

 the field to the refrigerator car is the great amount of latent heat 

 which the products carry into the car. Before refrigeration can 

 become effective the temperature of the vegetables or fruit must 

 be lowered by the refrigerating apparatus of the car to a point 

 below which destructive organisms work. Precooling supplements 

 refrigeration and makes it a more effective agency in transpor- 

 tation. Under the ordinary method of loading truck from the 

 % field to the car, enough time elapses, between loading and the cool- 

 ing of the mass in the car to allow ripening to progress, often to 

 the detriment of the shipment, particularly where long hauls are 

 involved. 



However, in order that precooling and ' transportation under 

 refrigeration may be most effective, it is absojutely essential that 

 only perfect products be handled. Precooling and shipment under 

 refrigeration cannot correct the effects of rough handling, bruising, 

 wilting of the products, or improper grading, particularly as regards 

 the stage of development and maturity of the products. In the 

 investigation which the Department of Agriculture has conducted 

 in the transportation of citrus fruits from California and Florida 

 to the Eastern markets, it has found that the losses in transit and 

 upon the market are due quite as much to mechanical injury to 

 the product before it was shipped as to any other cause. A per- 

 fect product one free from mechanical injury and from disease 

 even though it be a highly perishable one, can be successfully 



