Irradiation rocks, or «the apple experiment»
It certainly rocked whatever microorganisms had lived on my apple before the procedure. The ultimate proof you are asking for? Last year, I bought some tasty  UK apples that all but one got consumed by moi . Cleaning and emptying my fridge isn't especially one of my favourite pastimes and I don't stick to expiration dates anyway . Hence, the apple stayed in my fridge for a «good deal» of time - in fact, roughly four months by now. And thanks to the wonders of modern fruit treatment it still looks more or less appealing. If the apple was similar to the flavr savr tomato and had no pectinases I bet it'd be crunchy as well.
I am actually contemplating taking some smears from the surface and incubate them on plate count agar. Very tempting ...
 Let's claim they were tasty.
 Yes Emily, I also ate the cores.
 Unless as there's a green layer of moulds on top or the food starts moving it falls into the Mike-category «eatible».