In vitro gastric digestion antioxidant and cellular radical scavenging activities of wheat-shiitake noodles

A high glycaemic index diet causes a rapid increase in blood sugar level and may lead to chronic metabolic disorders such as obesity and type 2 diabetes. Shiitake is rich in bioactive compounds. Wheat flour noodles were enriched with shiitake (Lentinus edodes) powder (cap, stem, whole) at different levels to investigate the effects of shiitake addition on the nutritional composition, physical and textural properties. In vitro digestion was conducted to determine the glycaemic glucose equivalents and bioaccessibility of antioxidants in digesta. The addition of 15% shiitake stem powder in the noodles resulted in a significant (p < 0.05) decrease in reducing sugars released after in vitro digestion. Digesta also exhibited cellular antioxidant ability on IEC-6 cells after H2O2-induced oxidative stress. These results show the potential beneficial use of shiitake, especially the stem, as a high-value ingredient to improve the nutritional profile and reduce the glycaemic index of foods.