Ultrasound-assisted fermentation effectively alleviates the weakening of wheat gluten network caused by long-chain inulin and the underlying mechanism

[Display omitted] •The addition of 5 % FXL (Long-chain inulin) weakened the gluten network and hindered the formation of a dense network structure.•Ultrasound (250 W, 300 W) assisted fermentation can effectively improve the weakening of gluten network structure due to the addition of FXL.•Ultrasonic (250 W, 300 W) assistance restricts the moisture flow within the dough.•Ultrasonic treatment (250 W) facilitated the content of ordered β-sheets and promoted the transformation of disordered structures into ordered ones.•Ultrasonic assistance can be used to improve the quality of wheat products. The main objective of the article is to elucidate the effects of ultrasonic treatment with different ultrasonic power (0 W, 200 W, 250 W, 300 W, 400 W and 500 W) on the rheology, water distribution, sulfhydryl disulfide bond content, microstructure, and gluten properties of FXL (Long-chain inulin) dough. When the ultrasonic power is 300 W, the protein polymerization can be promoted, thus improving the gluten network. The mechanical action and cavitation induced by ultrasound changed the water distribution of FXL dough and promoted the transition from weakly bound water to tightly bound water. The T21 value (tightly bound water relaxation time) was shortened from 0.25 to 0.16 and the A21 (tightly bound water content) was reduced from 6.35 to 5.18, an improvement of 22.6 %, at a power of 300 W. Ultrasound decreased the enthalpy of FXL dough, and increased the particle size and potential of gluten protein. The introduction of ultrasound increased the content of β-sheets structure (40.85) at 250 W. The microstructure of the FXL dough revealed that ultrasonic treatment induced a continuous tight membrane-like gluten network, while the application of 500 W ultrasonic power resulted in the exposure and depression of starch particles.