Relaxation phenomena of radicals induced in irradiated fresh papayas

Kikuchi, Masahiro; Kakita, Daisuke*; Shimoyama, Yuhei; Ukai, Mitsuko*; Kobayashi, Yasuhiko

Electron spin resonance spectrometry of the -irradiated fresh papayas followed by freeze-drying and powderization was performed. We found a strong single peak in the flesh was observed at = 2.004 and attributed to organic free radicals. Using the method of Lund , relaxation times of the peak from 0 to 14 days-stored samples after -irradiation were calculated. T showed a dose response, while T kept almost constant by the increment of doses. The -radiation-induced radicals showing progressive saturation behaviors can be caused through a different pathway from indirect effects by the low LET radiations.