Citric acid is a weak organic acid that occurs naturally in citrus fruits such as lemons, limes, oranges, and grapefruits. It is a tricarboxylic acid with the chemical formula C6H8O7 and is commonly used as a food additive, preservative, and flavoring agent. Citric acid is also used in the pharmaceutical industry, as a chelating agent in cleaning and personal care products, and in the production of cosmetics and detergents. It is a white crystalline powder with a sour taste and is soluble in water.