Enhancement of physicochemical properties and antioxidant activities of bamboo shoot dietary fibers via γ-irradiation

• The modification of soluble and insoluble dietary fiber in Bamboo shoots of by γ-irradiation treatment were systematically studied. • The results show that γ-irradiation could greatly enhance the extraction yield of soluble dietary fiber by modifying insoluble dietary fiber. • A certain degree of irradiation enhanced the total antioxidant activity of bamboo shoots, and the ability to eliminate hydroxyl radicals further confirmed this view. The physicochemical, functional properties and antioxidant activity of dietary fiber from bamboo shoot after specific γ-irradiation were investigated. Compared with untreated samples, the water-oil properties (3 kGy) of dietary fiber and the adsorption capacity of nitrite (6 kGy), cholesterol (6 kGy) and glucose (3 kGy) were improved to some extent by certain doses of irradiation. The composition of dietary fiber changes after irradiation, mainly in the increase of soluble dietary fiber (SDF) ratio. FTIR analysis showed that the peak intensity of SDF decreased after irradiation, which might be due to the degradation of pectin or hemicellulose to reduce the hydrogen bond of dietary fiber. Combined with X-ray diffraction results, the crystalline region of dietary fiber was destroyed after irradiation, which lead to the increase of amorphous region ratio, which further explain the degradation of insoluble dietary fiber (IDF). Total antioxidant capacity and hydroxyl radical scavenging ability of SDF were significantly improved at 6 kGy. Stronger relationships between properties of bamboo shoots fibers and γ-irradiation were observed, which could furnish pieces of scientific evidence for the further application of bamboo shoots.