"Cleaner"? What an odd use of that word. Are you talking about bacterial concentrations? Are you talking about amount of soil contained in the food? I don't think there are differences based on those criterial. All types of human food will rot if left unpreserved.
I'd guess they mean cleaner of toxins, in reference to biomagnification. It's basically the reason I'm veg.
Toxins. I guess it's not obvious to everyone what I meant.
Communication is indeed difficult.