Both storage time and irradiation doses significantly (p < 0.05) affect the peroxide value of the control, which increased (p < 0.05) from 1.72 to 5.12 mEqO2 kg1 pistachio oil during the
12 months of storing. Immediately after irradiation, the higher absorbed doses of gamma irradiation (2 and 3 kGy) significantly (p < 0.05) decreased the PV of pistachio oil. Whereas, after 12 months of storage, the lower absorbed doses of gamma irradiation (1 and 2 kGy) significantly (p < 0.05) decreased the PV of pistachio oil comparing to the control samples.