Physicochemical and rheological properties of crude polysaccharides extracted from Tremella fuciformis with different methods

The crude polysaccharides obtained by different extraction methods have different uses in food and cosmetics, mainly due to the significant differences in physicochemical and rheological properties. Crude Tremella fuciformis polysaccharides (TPs) were extracted by five different methods: hot-water extraction (TP1), high-pressure water extraction (TP2), alkali extraction (TP3), acid extraction (TP4) and enzyme-assisted extraction (TP5). Their extraction yield, chemical composition, molecular weight, micromorphological structure and rheological properties were investigated and compared. They all were acid heteropolysaccharides with mannose as the main chain. Five TPs had similar dynamic viscoelasticity, exhibited viscous characteristics at low vibration frequencies and elastic characteristics at higher vibration frequencies. TP3, TP4 and TP5 solutions are not easily deformed and are suitable for applying in the products that require shape retention. This paper provides some theoretical data support for the scientific research of crude Tremella fuciformis polysaccharide and its application in food, medicine and cosmetics.