benzoat

Benzoate refers to the salt or ester of benzoic acid. The term often denotes sodium benzoate or potassium benzoate (salts) as well as esters such as methyl benzoate and ethyl benzoate (used as flavorings and fragrances). In chemistry, benzoate can describe the benzoate anion, C6H5COO−, which forms when benzoic acid loses a proton.

Chemically, benzoates are derived from benzoic acid (C6H5COOH). The benzoate ion has a pKa around 4.2, meaning it is largely deprotonated at neutral pH but can form benzoic acid in more acidic environments. Salts of benzoic acid are typically more water-soluble than the free acid.

Production and occurrence: Benzoates are produced by neutralizing benzoic acid with a base, or by esterification to form esters used in flavors and fragrances. Benzoic acid itself occurs naturally in various foods and plants and historically derives its name from benzoin resin.

Uses: The most common benzoate in food is sodium benzoate (E211), a preservative that inhibits molds and yeasts in acidic foods and beverages. Benzoates are also used as preservatives in cosmetics and medicines and as excipients in pharmaceuticals. Esters such as methyl benzoate and ethyl benzoate are valued for their aromatic properties.

Safety and regulation: Benzoates are generally recognized as safe when used within regulatory limits. In some individuals, sensitivity or allergies can occur. Under certain conditions, benzoates can form benzene, a potential carcinogen, when exposed to heat and light in the presence of ascorbic acid, leading to monitoring and risk assessment by food safety authorities.