THE EFFECT OF LOW-TEMPERATURE STORAGE AND 
FREEZING ON FRUITS AND VEGETABLES i 
LoN A. Hawkins 
(Received for publication March 25, 1922) 
The importance of low-temperature storage and refrigerated transporta- 
tion facilities for food products in the present state of our social and economic 
system can hardly be estimated. Enormous quantities of foodstuffs which 
might otherwise be unprofitably utilized or wasted outright are conserved 
each year by cold storage or are transported in refrigerated cars or ships 
from the localities where they are grown to communities where they can be 
utilized. Thus a diversity of diet ranging from tropical fruits to caribou 
flesh from the Arctic regions is made possible over a large part of the civilized 
world. The feeding of the large population in industrial centers is rendered 
much more economical, convenient, and sanitary by the proper application 
of low- temperature storage to food products. 
The mechanical problems of refrigeration have of necessity received 
much attention, and methods have been perfected whereby constant low 
temperatures can be readily maintained at a comparatively low cost. The 
effect of these temperatures on the produce has not received as much 
attention as the problems seem to warrant. There are, of course, consider- 
able data on the behavior of plant products under low temperatures, which 
have been obtained by empirical methods. These methods are probably 
not the best for determining the facts to be used as a basis for a great 
industry. With the inadequate facilities for careful experimentation and 
study of physiological problems, it has been the only way for obtaining 
much of the information urgently needed. 
Although the present status of our knowledge of the effect of low tem- 
peratures on living plant products leaves much to be desired, a survey of 
the field of plant physiology shows that some work has been done. It is 
the province of this paper to take up briefly some phases of the effect of 
low-temperature storage on fruits and vegetables. 
In the commercial storage of these products it is essential that they be 
kept in such a condition that that group of chemical and physical processes 
usually associated with living organisms and characterized for want of a 
better name as "life processes" or "vital activities" can proceed without 
interruption. At the same time, it is essential that these processes be 
slowed down as much as possible, so that this portion of the life cycle of the 
1 Paper read at the symposium on "The Low Temperature Relations of Plants," at 
Toronto, December 29, 192 1. 
