Polydextrose is a water-soluble polymeric compound formed by heat polymerization of corn extension glucose as the main polymer, citric acid as the catalyst and sorbitol as the plasticizer. Polydextrose as a new type of dietary fiber and thickening agent, expansive agent, formula assistant agent, filler, etc., is mainly used in low-energy, high-fiber and other functional foods. In fiber food, polydextrose is a main fiber source with more than 90% water-soluble dietary fiber content. In low-energy food, polydextrose can partially or completely replace sugar and fat, which can reduce the energy of food and maintain the original flavor and texture of food, bringing satisfying taste and enjoyment.