Citric acid is a weak organic tricarboxylic acid naturally occurring in citrus fruits. It functions as an acidity regulator in foods and beverages by lowering pH, enhancing flavor, and acting as a chelating agent to prevent oxidation. Widely used in soft drinks, jams, candies, and processed foods. It is produced industrially via fermentation of sugars by Aspergillus niger. Chemically stable under normal conditions, it decomposes upon heating above its melting point. As a GRAS substance, it is approved for food use by FDA and EFSA with no specified ADI. It contributes tartness and acts as a preservative by inhibiting microbial growth at low pH.