Can you mention any substances/foods for the bitter category (sour/salty/sweet if

[bluenblackstraw]

you want)? I'm trying to develop a fictional character who's power is dependant on taste. Sweets will make adhesives from sugars, Sourness gives him corrosive (acidity from citric fruit), salty will give him salt power but I'm not sure what salt can do (doesn't have to be fighting powers, any in general that can be useful). I know tonic water is bitter, but what can bitter things (quinine) and salts do?