超声协同大豆分离蛋白对米粉和米面包品质的影响及机制研究

目的 探究超声协同大豆分离蛋白(soybean isolate protein, SPI)对米粉以及米面包品质的影响。方法 以碎米为主要原料,5个梯度（0%、3%、6%、9%、12%,以碎米粉质量计）的大豆分离蛋白(soybean isolate protein, SPI)为辅料,比较超声协同5个梯度SPI对混合粉热机械学特性、糊化特性、流变特性以及米面包比容、损耗率、感官评价的影响。结果 与未进行超声处理的样品相比,超声协同SPI处理的米粉的吸水率从64.90±0.00增加至94.80±0.00,其混合粉的峰值黏度从2704.00±47.76降低至1567.00±116.73,表明超声使淀粉部分支链断裂,生成大量短直链淀粉,导致分子量下降,相互作用减弱;超声处理后的样品G′曲线呈现出先增加后降低的趋势,G''曲线随着SPI含量的增加呈现出逐渐降低的趋势。当SPI添加量为9%时,米面包的比容达到最大值,为0.86±0.08,感官评分从50.05±3.75增加至86.27±2.28分;当SPI添加量达到12%时,米面包的损耗率达到最低。结论 综上所述,采用9% SPI的方法制备米面包,可以有效的改善米面包品质,本研究为米面包在食品领域的应用提供了理论基础。

Effect of ultrasound synergized soybean isolate protein on the quality of rice flour and rice bread and its mechanism

Objective To investigate the effect of ultrasound synergized soybean isolate protein on the quality of rice flour as well as rice bread. Methods Using broken rice as the main ingredient and five gradients (0%, 3%, 6%, 9%, and 12% by mass of broken rice flour) of soybean isolate protein (SPI) as the excipient, we compared the effects of ultrasonically synergizing the five gradients of SPI on the thermo-mechanical properties, pasting properties, and rheological properties of the blended flour, as well as on the specific volume of the rice bread, the rate of loss, and the organoleptic evaluation. Results The water absorption of the ultrasound synergized SPI-treated rice flour increased from 64.90±0.00 to 94.80±0.00, and the peak viscosity of its blended flour decreased from 2704.00±47.76 to 1567.00±116.73 as compared to the non-ultrasounded samples, indicating that ultrasound broke some of the branched chains of the starch, generating a large number of short straight-chained starches, which resulted in a decrease in the molecular weight and a interactions were weakened; The G'' curves of the ultrasonically treated samples showed an increasing and then decreasing trend, and the G" curves showed a gradual decreasing trend with the increase of SPI content. At 9% SPI addition, the specific volume of rice bread reached a maximum value of 0.86±0.08 and the sensory score increased from 50.05±3.75 to 86.27±2.28; The loss rate of rice bread was minimized when SPI was added at 12%. Conclusion In conclusion, the preparation of rice bread with 9% SPI can effectively improve the quality of rice bread. This study provides a theoretical basis for the application of rice bread in the food sector.