Citric Acid, Sour Salt
Citric Acid is also called Sour Salt. These fine crystals give a puckery tartness, like lemon, to foods.
People on low sodium diets find this spice gives some of the same type of taste as salt. Citric acid is used in homemade lemonade mixes. The most common use for citric acid is in canning. It helps preserve and prevent discoloration.