Effects of Cordyceps polysaccharides on pasting properties and in vitro starch digestibility of wheat starch

Abstract

Pasting properties and in vitro digestibility of wheat starch added with Cordyceps polysaccharides (CPS) were studied in this research. Showing in the RVA and rheological measurements result, not only can CPS reduce the viscosity of wheat starch but inhibit its short-term retrogradation. By the measurement of leached amylose and scanning electron microscope (SEM), we found that CPS could reduce the starch gelatinization degree while retaining more complete starch granules by connecting with leached amylose, leading to the decrease of leached amylose. In the light of the results of fourier transform infrared (FT-IR), CPS combined with leached amylose via hydrogen bonds during the gelatinization, thereby preventing the re-aggregation of starch particles and inhibiting the short-term retrogradation of wheat starch. The results of in vitro digestion analysis strongly indicated that CPS could reduce the digestibility of wheat starch, which might be related to the inhibition of starch gelatinization. Suffice it to say, CPS can prevent wheat starch from gelatinization, inhibit its short-term retrogradation and reduce the wheat starch digestibility. These results can be helpful to the application of CPS in starch-based functional foods.