In recent years, almond has been considered as one of the most common alternative plant-based protein sources due to its nutritional attributes and health benefits. However, almond protein has a lower digestibility compared with the animal protein. The objective of this study is to investigate the impact of pulsed high-intensity ultrasound on the secondary structure of the almond protein. The changes in the in-vitro protein digestibility (IVPD %) are also evaluated to investigate the relationship between the structure and digestibility of the almond protein. The secondary structures were analyzed using Fourier-transform infrared spectroscopy (FT-IR) and circular dichroism (CD) spectroscopy. FT-IR analysis showed a slight relocation in the ordered and unordered structures in the ultrasonicated almond protein compared to the control. CD spectroscopy revealed that ultrasound resulted in the restructuring of α-helices into β-sheets. However, upon treating the almond protein for 16 min, a slight recovery in α-helices was observed. Moisture content was found to affect the secondary structure orientations of almond protein significantly. Although the IVPD% change was not statistically significant, it was found to be increasing slightly with processing duration and was dependent on protein secondary structure.

近年来，由于杏仁的营养特性和健康益处，杏仁被认为是最常见的基于植物的替代蛋白质来源之一。但是，杏仁蛋白比动物蛋白具有较低的消化率。本研究的目的是研究脉冲高强度超声对杏仁蛋白二级结构的影响。体外的变化还评估了蛋白质的消化率（IVPD％），以研究杏仁蛋白的结构与消化率之间的关系。使用傅立叶变换红外光谱（FT-IR）和圆二色性（CD）光谱分析二级结构。FT-IR分析显示与对照相比，超声杏仁蛋白中有序和无序结构中的轻微重新定位。CD光谱显示超声导致α螺旋重组为β折叠。但是，将杏仁蛋白处理16分钟后，观察到α螺旋的轻微恢复。发现水分含量显着影响杏仁蛋白的二级结构取向。尽管IVPD％的变化在统计学上不显着，