Structure, physicochemical, and in vitro functional properties of insoluble dietary fiber from bamboo culm: A potential functional ingredient

Bamboo culm contains abundant hemicellulose, cellulose, and lignin, which was a high-quality insoluble dietary fiber (IDF) raw material. In this paper, the effects of alkaline hydrogen peroxide (AHP) and enzymatic hydrolysis on physicochemical and functional of bamboo IDF (named BIDF and OIDF, respectively) were reported. SEM, FT-IR, and XRD analysis suggested that both BIDF and OIDF had the functional groups of insoluble cellulose and crystal structure of cellulose. AHP treatment effectively improved the water-holding capacity (WHC), water swelling capacity (SC), and glucose absorption capacity (GAC). Enzymatic hydrolysis effectively improved the glucose dialysis retardation index (GDRI), bile acid salt absorption capacity (BAC), cholesterol-adsorption capacity (CAC), and nitrite ion absorption capacity (NIAC). In addition, they all exhibited great toxic ions adsorption (Cd2+, Pb2+). The above results showed that bamboo culm IDF could be used as an ideal functional ingredient in food processing. Practical applications Insoluble dietary fiber (IDF) provides various beneficial functions, such as hypoglycemic and hypolipidemic. We used alkaline hydrogen peroxide treatment (AHP) and complex enzymatic hydrolysis to improve the physicochemical and functional properties of bamboo IDF and help to the further research on its application value in food and other industry. The bamboo culm IDF could be incorporated into other food products for enhancing textural properties and promoting a favorable mouthfeel and it was an ideal functional ingredient in food processing.