im six months late, (forgot about lemmy) but i did test it, i looked at something i never touched that would probably be fine to lick, and licked it. Probably doesn't work all the time.
You might be surprised. Investigation into Molyneux's Problem found that people born blind, who later had their sight restored, could not identify by sight the objects they already knew by touch.
I've seen plenty of jelly fish but I can't really fathom what it would feel like to lick one. Would it be smooth but spicy? Would it be prickly? Would it be slimy? IDK!