Sure irradiation can reduce the PPO based browning.

Of course, irradiation can inactive PPO from fruit and vegetable.

In china, there are some researches about the effect of irradiation on PPO.

Polyphenol oxidase is an enzyme which, depending on the dose of irradiation and duration in the chamber, could be affected. A simple confirmatory test for PPO should be carried out as a post-irradiation step for fruit and vegetables.

Thanks for sharing your views and experiences.