OZONE IN RELATION TO STORAGE OF APPLES 



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Figure 4. — Effect of intermittent high concentrations of ozone in the air on the spore 

 population of Penicillium expansion introduced into a storage room as indicated by 

 the colonies developing on nutrient-agar plates exposed for 30 minutes: A, Plate 

 exposed 4 hours after spores had been introduced; B, plate exposed after the room 

 had been ozonized for 2% hours and the ozone concentration had reached 33.9 

 p. p. m.; C, plate exposed 16 hours after that shown in B without any addition of 

 ozone; D and E, plates exposed after i l / 2 and 6 l / 2 hours, respectively, of additional 

 ozonization during which the concentration of ozone reached 50.4 p. p. m. ; F, plate 

 exposed 16 hours after that shown in E without any addition of ozone. 



