Slightly off topic, but years ago, I worked with a chap who'd been in the Royal Navy soon after WW2, and he told me that they used to drink oatmeal!
The idea was that you filled a kit-bag with the stuff, topped it all up with water, and hung it from the ceiling.
The water would slowly seep through the canvas of the kit-bag, and by evaporation, cooled the contents down considerably, especially in the hot area below decks!
I've never tried it, but it sounds rather pleasant somehow!