Citric acid is a compound originally derived from lemon juice. It is produced from a specific type of mold and used for a variety of applications. These are acidic, sour tasting in nature, citric acid that is predominantly used as a flavoring and preserving agent, especially in soft drinks and candies. These are tricarboxylic acids found in citrus fruits. Citric acid is used as an excipient in pharmaceutical preparations due to its antioxidant properties. It is the main stability of active ingredients and is used as a preservative.