【摘要】 采用超声技术对豌豆蛋白进行改性,利用单因素实验考察超声功率、超声时间和豌豆蛋白质量浓度对豌豆蛋白乳化性的影响,采用正交实验优化改性条件。通过傅里叶红外光谱和激光粒度分布仪对改性产物进行表征,采用显微镜进行微观结构观察。结果表明:豌豆蛋白超声改性最佳工艺条件为豌豆蛋白质量浓度30 mg/m L、超声时间40 min、超声功率500 W,在此条件下超声改性豌豆蛋白乳化活性(A₅₀₀)为0. 331,乳化稳定性为72. 52%;超声改性豌豆蛋白的α-螺旋和β-转角含量减少,β-折叠和无规卷曲含量升高,表明超声改性破坏了蛋白质空间结构,进而改善了豌豆蛋白的功能性;超声改性豌豆蛋白乳状液于4℃储藏15 d无明显絮凝现象。更多还原

【Abstract】 The pea protein was modified by ultrasonic technology. The effects of ultrasonic power,ultrasonic time and mass concentration of pea protein on the emulsifying properties of pea protein were investigated by single factor experiment,and then the modification conditions were optimized by orthogonal experiment. The characterization of the product was conducted by Fourier transform infrared spectroscopy and laser particle sizer and the microstructure was observed by microscope. The results showed that the optimal modification conditions of pea protein were obtained as follows: ultrasonic power 500 W,ultrasonic time 40 min,mass concentration of pea protein 30 mg/m L. Under these conditions,the emulsifying ability (A₅₀₀) and emulsion stability of modified pea protein were 0. 331 and 72. 52% respectively. The contents of α-helix and β-turn reduced,and the contents of β-fold and random coils increased,which indicated that the modification destroyed the spatial structure of the protein and thus improved the functionality of the pea protein. There was no obvious flocculation phenomenon when the modified pea protein emulsion was stored at 4 ℃ for 15 d.更多还原