What Is Curdlan? Applications, Dosage, Alternatives & Specifications

Curdlan is a new highmolecularweight polymer produced by microbial fermentation of sugar raw materials. It is a waterinsoluble glucan with extensive application value in the global food industry, pharmaceutical, and biomaterial fields. It is the third fermented food polysaccharide approved by the FDA after xanthan gum and gellan gum. Its molecular formula is generally expressed as (C6H10O5)n, with n approximately 400–500, CAS number is 54724–00–4, EINECS number is 232–712–4, CNS number is 20.042, and INS number is 424. Curdlan was discovered in 1966 by Professor Harada‘s team at Osaka University, Japan, during research on Acetobacter. The team isolated a bacterium named Alcaligenes faecalis var. myxogenes (10C3) from soil and found that this bacterium could produce a new type of polysaccharide during culture. This polysaccharide suspension could form a Curdlelike solid upon heating, and was therefore named “Curdlan”. In terms of chemical structure, Curdlan is a linear, unbranched glucan composed of approximately 400 to 500 Dglucose residues connected by β-1,3-glycosidic bonds. This unique linear β-1,3-glucan structure endows Curdlan with a special function not found in other food gums. Curdlan appears as a white to offwhite powder, odorless and tasteless, with good flowability and excellent stability in the dry state. It is insoluble in water, ethanol, and other organic solvents, but is easily dispersible in cold water to form a homogeneous suspension. It is completely soluble in alkaline aqueous solutions with pH above 12. When a 1% aqueous suspension is heated from 54°C to 78°C and then cooled to below 40°C, a thermoreversible lowset gel forms. When the suspension is heated to above 80°C, a firm, thermally irreversible highset gel forms, which does not dissolve even when reheated to 130°C. Compared with other food gums, Curdlan maintains its stable gel structure and good elastic texture under hightemperature processing and cooking conditions above 80°C. Its gel strength increases with higher heating temperatures and longer heating times. Curdlan is stable to light, heat, and air, is not digested or absorbed by the human body, produces no calories, and contains approximately 98% dietary fiber.

Curdlan is known as a nextgeneration thermally irreversible food gum, an innovative functional ingredient in the modern food industry and healthy food fields. Its most outstanding core advantages lie in its unique thermoreversible/thermally irreversible dual gelling properties, and its excellent heat resistance, freezethaw stability, and formulation synergy. Unique Thermoreversible/Thermally Irreversible Dual Gelling Properties: The most distinguishing feature of Curdlan is that its gelling properties can be flexibly switched by precisely controlling the heating temperature. When the aqueous suspension is heated to 55–65°C and then cooled to below 40°C, a thermoreversible lowset gel forms. When heated to above 80°C, a firm, thermally irreversible highset gel forms, which does not dissolve even when reheated to 130°C. Excellent HighTemperature and FreezeThaw Stability: Curdlan gel has exceptional thermal stability, maintaining its structure and elastic texture under hightemperature conditions such as cooking, frying, and microwaving. It withstands temperatures up to 130°C without melting. The gel structure does not change during freezethaw cycles.

Excellent Water Retention and Food Texture Improvement: Curdlan is an excellent waterretention agent, stabilizer, and gelforming agent. It significantly improves waterholding capacity and firmness in meat products, adds elasticity and chewiness to noodle products, and prevents thickening and turbidity in broths.