This is something Catholics believe in and non-Catholics don’t normally investigate. It is one of those issues that has to be answered with a resounding maybe. Would a residue of acetone be able to overcome the otherwise normal accumulation of stinky compounds like putrescine? Not even religious ecstasies could do that. In general, God seems to accommodate willingness to believe with phenomena that addresses it. Since it is not an evangelical trope, God does not bother in that milieu.
I’m kind of surprised that the biblical reference of the saints as being a spiritual fragrant offering to God the Father by God the Son isn’t well noted here.
Not just Catholics. Buddhists talk about the exact same phenomena. “High level” monk’s bodies will remain incorrupt even many years after passing, and they will emit the smell of flowers. The similarities between the two religions are striking in this regard.
I’ve even visited several temples/monastaries in Asia where a saint or previous teacher’s incorrupt body will be on display, sometimes covered with gold foil.