A class of chemical molecules known as citrate esters is generated from citric acid, which is an essential component of the citric acid cycle and is essential to cellular metabolism. Citric acid reacts with an alcohol, usually a short-chain alcohol like methanol or ethanol, to generate these esters. Thanks to their emulsifying, stabilizing, and flavor-enhancing qualities, they find several uses in the food, pharmaceutical, and cosmetics sectors.Triethyl citrate (TEC), which is created when ethanol and citric acid are esterified, is one of the most widely used citrate esters. TEC is a colorless, odorless liquid that dissolves very minimally in water but is miscible with a wide range of organic solvents. It is frequently employed as a plasticizer in the manufacturing of coatings for pharmaceuticals, food packaging, and cosmetic products. TEC functions as a plasticizer that enhances the processing properties, flexibility, and durability of polymers. Tributyl citrate (TBC), which is created when butanol and citric acid are esterified, is another significant citrate ester. TBC is a poor water solubility, colorless, and odorless liquid. It is frequently employed as a plasticizer in the manufacturing of products made of cellulose, including sheets, films, and coatings. These materials get flexibility and durability from TBC, which qualifies them for use in toys, medical equipment, and food packaging. Because they are amphiphilic, citrate esters are also used as surfactants and emulsifiers. They have the ability to stabilize emulsions and lower surface tension in liquid formulations due to their hydrophilic citrate moiety and hydrophobic alkyl chains. For instance, glyceryl citrate/lactate/linoleate/oleate (GCLLO), a citrate ester, is frequently utilized in cosmetic formulations, including lotions, creams, and hair care items. These esters facilitate the production of stable emulsions, promote the transfer of active substances to the skin or hair, and improve texture. In conclusion, citrate esters are adaptable substances with a variety of uses across multiple industries. Their versatility as plasticizers, emulsifiers, and stabilizers makes them useful additions to a wide range of product formulations. Citrate esters' potential for novel and creative applications is expected to grow as research is conducted, underscoring their significance in the chemical and manufacturing industries.
