Effects of ultrasonic assisted high-temperature cooking method on the physicochemical structure characteristics and in vitro antioxidant capacities of dietary fiber from Dendrocalamus brandisii Munro shoots

In this study, the ultrasonic assisted high-temperature cooking extraction method of soluble dietary fiber from bamboo shoots was optimized by response surface methodology, and the effects of ultrasonic assisted hightemperature cooking extraction on the structural characteristics, physicochemical properties and antioxidant activity of soluble dietary fiber (SDF) from bamboo shoots were evaluated. The yield of modified UH-SDF1 was significantly higher than that of untreated D-SDF2. FTIR and XRD confirmed that UH-SDF had more hydrophilic groups and higher crystallinity (28.73 %), resulting in better thermal stability. SEM observation showed that UHSDF exhibited a more loose microstructure, and the particle size of UH-SDF (601.52 & mu;m) was significantly smaller than that of D-SDF (242.59 & mu;m), so UH-SDF had a larger specific surface area. In addition, UH-SDF has stronger water holding capacity, water swelling capacity and oil holding capacity than D-SDF. The DPPH radical and hydroxyl radical scavenging rates of UH-SDF were 8.91 % and 7.49 % higher than those of D-SDF. In addition, the reducing ability of UH-SDF was higher than that of D-SDF, which had better antioxidant activity. In summary, UH-SDF has the potential to be developed as an anti-inflammatory functional food.