An ultrasound-assisted alkali method was developed to obtain high extraction level of pea protein isolate (PPI). The method parameters of ultrasound-assisted alkali extraction were successfully optimized using response surface methodology. The highest extraction level of PPI reached 82.6% at a solid/liquid ratio of 1:11.5 g:mL, pH 9.6, 13.5 min extraction time and 33.7% ultrasonic amplitude. Ultrasound caused changes to the secondary and tertiary protein structure of PPI, resulting in partial protein unfolding and the exposure of hydrophobic groups. In addition, smaller particle size and better dispersion were obtained in PPI with ultrasound-assisted extraction. The ultrasound-assisted alkali method resulted in significant improvements in the functional properties of PPIs, including increased solubility, water/oil holding capacity, foaming/emulsifying capacity, stability, and gel formation capacity. The biological activities of PPIs were also enhanced. Hydroxyl radical scavenging capacity was doubled, and angiotensin-converting enzyme inhibitory activity was increased by 55.1% compared with those of PPI extracted using traditional method. This study provides a potential strategy for the production of pea protein with high efficiency and high quality.

开发了超声辅助碱法以获得高提取水平的豌豆蛋白分离物（PPI）。响应面法成功地优化了超声辅助碱提取的方法参数。在固液比为1：11.5 g：mL，pH 9.6，提取时间为13.5 min和超声幅度为33.7％的情况下，PPI的最高提取水平达到82.6％。超声波导致PPI的二级和三级蛋白质结构发生变化，导致部分蛋白质解折叠和疏水基团暴露。此外，超声辅助萃取在PPI中获得了更小的粒径和更好的分散性。超声波辅助碱法大大改善了PPI的功能特性，包括增加的溶解度，保水/保油能力，发泡/乳化能力，稳定性和凝胶形成能力。PPI的生物学活性也得到增强。与传统方法提取的PPI相比，羟基自由基清除能力提高了一倍，血管紧张素转化酶的抑制活性提高了55.1％。这项研究为高效高效地生产豌豆蛋白提供了潜在的策略。