My Dad has been in Dialysis for almost a year, His Diet is specific, no sodium, photasium or phosphorus, sometimes when He eats bread or anything with a little bit of sodium, I would say 210 mg in on piece of flour tortilla or bread, He complains of producing or having salt in his mouth, or somehow producing pebbles of salt. Is this even possible?

He blames the bread or anything he eats with some amount of a little bit of salt.