Surfactants are surface-active agents whose molecules combine a hydrophilic head with a hydrophobic tail, allowing them to sit at interfaces and reduce surface tension. In foods they appear as emulsifiers such as lecithin, mono- and diglycerides, and polysorbates that stabilize mayonnaise, ice cream, and baked goods; as foaming and whipping agents; and as the detergents that clean processing equipment. Beyond foods they serve in textiles, paper, and antifreeze formulations. Their selection balances effectiveness, regulatory approval, flavour neutrality, and increasingly, consumer preference for naturally derived options.