Physicochemical properties of Tremella fuciformis polysaccharide and its interactions with myofibrillar protein

Tremella fuciformis, belonging to the tremellaceae, was known as an edible and medicinal fungus in China. A polysaccharide fraction (TPS) in Tremella fuciformis was extracted by hot water and its physicochemical as well as rheological properties were investigated in the study. Results showed that TPS contained 0.72% (w/w) uronic acid, 0.60% (w/w) protein and 92.17% (w/w) total sugar, while consisted of rhamnose, xylose, mannose and glucose in the molar ratio of 1.13: 1: 4.70: 0.81. Results of rheological test demonstrated that TPS exhibited properties of pseudoplastic fluids in distilled water and could form weak gel in high frequency at 25°C. Meanwhile, it was found that TPS could significantly enhance the gel hardness and water-holding capacity (WHC) of myofibrillar protein gels. Besides, elasticity of myofibrillar protein gels was improved considerably by adding TPS. IR spectrum analysis of myofibrillar protein-TPS gels indicated that TPS decreased the wave number of N-H and O-H stretching peak between 3000 and 3500 cm−1, suggesting that TPS could enhance hydrogen bonding in myofibrillar protein gels. This study suggests that TPS may have an extensive prospect in the processing of low-fat meat products.