Dipotassium phosphate

Dipotassium phosphate is the inorganic compound with the formula K₂HPO₄^._x. Together with monopotassium phosphate, it is often used as a fertilizer, food additive, and buffering agent. It is a white or colorless solid that is soluble in water.
It is produced commercially by partial neutralization of phosphoric acid with two equivalents of potassium chloride:

Uses

As a food additive, dipotassium phosphate is used in imitation dairy creamers, dry powder beverages, mineral supplements, and starter cultures. It functions as an emulsifier, stabilizer and texturizer; it is also a buffering agent, and chelating agent especially for the calcium in milk products.
As a food additive, dipotassium phosphate is generally recognized as safe by the United States Food and Drug Administration, and is commonly used to add taste to some brands of bottled water.