208 



Journal of Agricultural Research 



Vol. XVI, No. 8 



TEMPERATURE CHANGES AS A MEANS OE AERATION 



Apples held at a constant temperature have usually scalded worse 

 than those exposed to temperature changes, the beneficial effects of 

 the fluctuating temperature apparently being due to the aeration of 

 the apple tissue thus obtained. Experimental results on this point 

 are given in Table IX. 



All of the apples were held in moist chambers and were therefore 

 poorly aerated. 



Table IX. — Influence of temperature changes upon apple scald 



The results in experiments i and 2 indicate that the amount of scald 

 was decreased by moving the apples from one temperature to another 

 during the first weeks of storage. The apples were given no aeration 

 at the time of change, and a probable explanation of the beneficial 

 effects resulting from shifting the apples from one temperature to 

 another seems to be some sort of renovation of intercellular air condi- 

 tions accompanying the temperature changes in the tissues. The 

 apples stored first at 5° and then at 0° had less scald and were of better 

 quaUty than those stored first at 0° and then at 5° or than those stored 

 continuously at 0°. 



In experiment 3 the apples were held part of the time at a temperature 

 (25° C.) that has been proved to be too high for the production of scald. 

 Other experiments have been made in which aeration has been combined 

 with high temperature with decidedly beneficial results in scald pre- 

 vention. In an earlier paper ^ an instance was reported in which scald 



1 Brooks, Charles, and Cooley, J. S. effect of temperature, aeration, and humidity on jona- 

 THAN-SPOT and scald OF APPLES IN STORAGE. In Jour. Agr. Research, v. 11, no. 7, p. 287-318, 23 fig., pi. 

 3^-33. 1917. Literature cited, p. 316-317. 



