In cosmetology, various formulas designed to treat the skin superficially or in depth are composed of several ingredients. Among the Alpha-Hydroxy-Acids or AHA, you will find citric acid which contains sodium citrate. This is generally used to regulate the pH of skincare products.
What is "Sodium Citrate" and what is its utility?
What is sodium citrate?
Known by its INCI (International Nomenclature of Cosmetic Ingredients) name Sodium Nitrate, Sodium Citrate is one of the sodium salts found in citric acid. It is also referred to as trisodium citrate. Generally, citric acid is present in most fruits, but on an industrial scale, it is extracted from the Aspergillus Niger fungus that is cultured and micro-fermented on a sugary solution. It can also be obtained through the synthesis of chemical agents or through the biotechnology of plant-based raw materials such as corn, tapioca, cassava, or sweet potato.
For household use, citric acid, which contains sodium citrate, is used for descaling various types of appliances or different surfaces, such as coffee machines, kettles, faucets, or surfaces made of chrome, ceramic, or steel. It is also a component in non-alcoholic refreshing beverages. In the field of cosmetology, citric acid is incorporated into exfoliating skincare treatments.
Sodium Citrate: Its Utility
The sodium salt of citric acid is typically used as a pH regulator in skincare. Its role is to stabilize or adjust the pH of a formula in order to neutralize unpleasant odors or the proliferation of potential bacteria that may embed themselves. This ingredient also corrects excessively high pH in foaming skincare products.
Sodium citrate also serves as a chelating agent in skincare products such as creams, washes, and others. It has the ability to bind positive ions to form a stable complex called a chelate, which prevents interaction between metallic cations and other ingredients in the product. Without the chelating agent, the cations can alter the stability of the emulsion as well as the pH of the formula, indirectly promoting oxidation or rancidity of the product.
Sodium citrate also serves as a masking agent that reduces and/or conceals the base odor of the skincare product.
Citric Acid: In Which Skincare Products?
Citric acid is found in the majority of beauty care products. As for those intended for the skin, you will find this ingredient in the formulas used regularly. For instance, it is part of the ingredient list of a serum designed for the treatment of blemished skin. Besides its properties in pH regulation, chelation, or masking, citric acid contributes to the effectiveness of the other ingredients in the skincare product. Acting against bacteria, it reduces and prevents the onset of pimples, pore blockage, and the appearance of blackheads by working in conjunction with salicylic acid and/or zinc, for example. Citric acid can also be among the ingredients of a skincare product indicated for oily skin or acne-prone skin.