Norman Potting
Well-known member
That's a myth. I've tried to clean money that way and it doesn't work. There is a slight difference where the liquid has permeated the grime (like leaving anything to soak), but they're no cleaner than if you soak them in washing up liquid.
On a similar line my dad was in the navy during the war and he never drank plain water as he'd seen what it did to the outside of battleships.
Brown sauce is also good for cleaning coins.