Save on Frontier Herb 1X 3.52 Oz Cream Of TartarCream Of Tartar Powder (Potassium Hydrogen Tartrate) Or Tartaric Acid, Is An Effervescent Acid Obtained As A By-Product Of Wine Making. The Acidic Powder Is Used For Culinary And Other Household Purposes, Among Them: Stabilizing Egg Whites.