organic sodium salt copolymer macromolecule sodium alginate Codex::401 A copolymer macromolecule composed of homopolymeric blocks of 1→4-linked homopolymeric blocks of 1→4-linked sodium β-<small>D</small>-mannuronate and sodium α-<small>L</small>-guluronate residues, covalently linked together in different sequences or blocks. The sodium salt of alginic acid. Europe::401 LanguaL term definition: Food additive; technological purpose(s): bulking agent, carrier, emulsifier, foaming agent, gelling agent, glazing agent, humectant, sequestrant, stabilizer, thickener. food additive