OZONE IN RELATION TO STORAGE OF APPLES 



21 



Table 10. — Injury to apples stored at 31° F. and exposed to 3.25 

 p. p. m. of ozone for various periods 



Variety and description of fruit 



Date of 

 examina- 

 tion 



Length of 

 time in 

 presence 

 of ozone 



Fruit injury 



Slight 



Severe 



Golden Delicious 



Delicious 



Arkansas: 

 Red fruit 



Jan. 12___ 

 Mar. 3___ 



JApr. 28 L_ 



\Mar. 3___ 

 /May 24 __ 



Days 

 73 

 123 



179 



119 

 205 



Percent 

 

 11 



/ 31.5 



I 28.6 

 

 10 



Percent 

 100 

 1.3 



67. 8 



Green fruit _ 



17. 4 



Winesap 













1 Held 1 week at 70° F. after removal from storage. 



2% hours ; a concentration of 33.9 p. p. m. was reached. The apples 

 removed from the room the following morning showed no injury. 

 After a few days, however, severe injury was manifest. These results 

 were in sharp contrast with Ewell's statement (6) that even 50 p. p. m. 

 has no deleterious effect upon apples. Concentrations of more than 

 10 p. p. m. for even a relatively short period of storage (a few weeks) 

 might induce injury on some varieties of apples, according to Smock 

 and Watson (&£) and Watson (27) . Gane (12) found that 11 p. p. in. 

 of ozone for 21 days produced injury on crab apples. It is interesting 

 to note that some investigators found ozone injury on bananas (11) 

 after exposure to 1.5 p. p. m. for 10 days and on Hale Haven peaches 

 after exposure to 5 p. p. m. for 2 weeks (24-) . 



Flavor 



No difference was noticed in the flavor of the ozonized and non- 

 ozonized fruit of Delicious, York Imperial, and Winesap varieties 

 during the 1941-42 season when the ozone concentration averaged 1.95 

 p. p. m. The ozonized Golden Delicious apples, however, were supe- 

 rior in flavor to the nonozonized fruit and possessed a more pleasant 

 aroma. No storage flavor was detected in the ozonized lots, whereas 

 it was of frequent occurrence in the nonozonized ones. 



However, at the higher concentration of ozone (3.25 p. p. m.) used 

 during the 1942-43 storage season definite impairment of flavor oc- 

 curred in most of the fruit. A musty flavor which became especially 

 objectionable in the Arkansas and Winesap varieties developed. It 

 was present to a less degree in Delicious and York Imperial also. 

 No objectionable flavor was noticed in Golden Delicious. However, 

 they were removed from storage at the end of their storage season 

 in January and so were not subjected to the ozonized atmosphere 

 as long as were the other varieties. 



Appearance 



A shiny, sticky, varnishlike cuticle was noticeable on the ozonized 

 Arkansas and Winesap varieties on March 3, 1943, and was very 

 pronounced at the end of the test in late May. This characteristic 



