Disclosed are carboxylic acid esters of alternan processes for preparing the ester an emulsifier which is the ester an emulsion comprising the emulsifier a composition comprising the ester a process for preparing a composition comprising either the acid, the emulsifier or the emulsion the use of the ester as a surfactant the use of the ester, emulsifier or emulsion for the preparation of foods, cosmetics or pharmaceutical compositions. Alternan is a polysaccharide composed of glucose units. The glucose units are linked with one another via alpha-1,6- and alpha-1,3 glycosidic bonds, with these two types of bond occurring predominantly alternating.
