Effect of high intensity ultrasound on transglutaminase-catalyzed soy protein isolate cold set gel

•TGase-catalyzed soy protein cold set gels (TSCGs) were formed at low temperature.•High intensity ultrasound (HIU) of SPI changed physicochemical properties of TSCG.•HIU increased the gel strength, water holding capacity and gel yield of TSCG.•HIU changed the microstructure and conformational structure of TSCG.•More inter-molecular covalent and non-covalent bonds may be formed after HIU.