Effect of Ultrasonic Treatment on Structure and Solubility of Soybean Lipophilic Protein

Abstract:

Aiming to investigate the effects of ultrasonic treatment on the structure and solubility of soybean lipophilic protein (LP). The extracted LP was ultrasonically separated under different conditions, and the effect of ultrasonic treatment on the structure and solubility of LP was analyzed by using sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE), Fourier transform infrared spectroscopy (FITR), endogenous, exogenous fluorescence intensity and differential scanning calorimetry (DSC). The results showed that SDS-PAGE showed that the ultrasonic treatment could not change the molecular weight distribution of LP, but could change the content of subunits, infrared spectrum and endogenous and exogenous fluorescence spectra. It was showed that different ultrasonic treatment conditions had different effects on the second and third structures of LP. With the increase of ultrasonic intensity, αhelix was firstly decreased and then increased, βfold was increased first and then decreased. The endogenous and exogenous fluorescence intensity was the strongest when treated at 360W ultrasonic power for 10min, and the thermal stability and solubility of LP were improved after treatment with 360W ultrasonic power for 10min and 240W ultrasonic power for 20min. The denaturation temperature was increased by 6~7℃, the solubility was increased by 20 percentage points, and it would have a negative impact on the functional properties of LP when the ultrasonic power was too large. Combined with the test results, it was concluded that the physicochemical properties of LP were most suitable for food applications after treatment at 360W ultrasonic power for 10min.