High moisture extrusion of soybean protein isolate: Effect of β-glucan on physicochemical properties of extrudates

•High moisture extrusion of SPI with BG is explored for the production of vegetable protein meat.•Extrudates containing 4% BG have well ordered and stabilized structures.•The increase in the content of ɑ-helix + β-sheet promotes the formation of ordered structure.•S2 and S1-S2 maintained the interaction between BG and SPI. This study is focused on exploring the effect of twin-screw high-moisture extrusion technology on the physico-chemical properties of β-glucan-soybean protein isolate (SPI-BG) extrudates. Different proportions (0 %, 1 %, 2 %, 3 %, 4 %, 5 %) of oat β-glucan (BG) were added with soybean protein isolate (SPI) to prepare SPI-BG extrudates. Results showed that the addition of a high quantity of β-glucan (BG) decreased the elastic properties of soy protein isolate (SPI) extrudates and then increased. The strengthening of S1-S2-S3 interactions (hydrogen bonds, hydrophobic interactions, and disulfide bonds) was primarily responsible for this trend. Fourier transform infrared (FTIR) spectral analysis was conducted which revealed that BG did not significant affect random coil content of SPI. However, it was observed that α-helix content was increased significantly and the β-sheet content was decreased. An observation was noted in the value of enthalpy (ΔH) change that increased from 115.80 J/g to 159.68 J/g.