Citric acid anhydrous is a white crystalline powder that is derived from citrus fruits such as lemons, limes, and oranges. It has a sour taste and is widely used in the food industry as a flavor enhancer and preservative. It can also be found in various household products such as cleaning agents and personal care items. Citric acid anhydrous is different from citric acid monohydrate, which contains one water molecule per citric acid molecule.