Citric Acid
Citric Acid is a naturally occurring alpha-hydroxy acid (AHA) with the molecular formula C₆H₈O₇ and a molecular weight of 192.12 g/mol, derived from citrus fruits such as lemons, limes, and oranges. In skincare formulations, it serves as a multifunctional ingredient that functions as a pH adjuster, chelating agent, chemical exfoliant, and preservative enhancer. This colorless, crystalline powder has a naturally acidic pH of approximately 2.2 when dissolved in water, making it highly effective at lowering the pH of cosmetic products to optimize their stability and compatibility with the skin’s natural acid mantle (pH 4.5-5.5). As an AHA, citric acid gently exfoliates the skin by dissolving the bonds between dead skin cells, promoting cellular turnover and revealing smoother, brighter skin while helping to unclog pores and reduce the appearance of hyperpigmentation. Its chelating properties bind metal ions that could otherwise destabilize formulations, while its antioxidant effects help protect against environmental damage and extend product shelf life. Citric acid is considered safe for use in cosmetic products at concentrations up to 10% with a minimum pH of 3.5, making it suitable for all skin types when used appropriately.
