When the temperature is low, the ability to dissolve and penetrate the polysaccharide is low, and the polysaccharide of S. birch is not easy to dissolve effectively. When the temperature is higher, the high temperature "disintegrates" the cells and enhances the molecular thermal movement, which promotes the degradation of some polysaccharide chains to be more soluble. However, when the temperature is too high, it will destroy the polysaccharide composition and cause degradation of the polysaccharide, which will lead to a decrease in the extraction rate [7].