Qi Wen, Zhou Bin, Zhang Jinhao, Liu Shen, Lu Binglin, Sun Ying, Zhang Na, Jiang Lianzhou
College of Food Engineering, Harbin University of Commerce, Harbin 150028, China.
Tourism & Cuisine College, Harbin University of Commerce, Harbin 150028, China.
Int J Biol Macromol. 2025 Aug;319(Pt 2):145358. doi: 10.1016/j.ijbiomac.2025.145358. Epub 2025 Jun 20.
The study investigated the gel properties and interaction mechanism of soy protein isolate (SPI) and potato protein (PP) composite gel. Results showed that increasing the proportion of PP could enhance the turbidity and surface hydrophobicity (H), facilitate the transition from random coil to β-sheet, strengthen both electrostatic and hydrophobic interactions, and decrease the disulfide bond content. This revealed that the interaction of the composite gel was enhanced after adding PP, and a more complex secondary structure was formed. Moreover, proteomic and electrophoresis analysis revealed that specific SPI subunits (P26987, Q96452, P02520, Q948P5, Q39839, P02580, P50346, and P69325) were irreversibly denatured in SPI/PP 70:30 composite gel, forming new protein segments (30-45 kDa and 70-90 kDa). Notably, SPI/PP 70:30 composite gel had the highest solubility, water-holding capacity (WHC), storage modulus (G') value, bound water content, gel strength and elasticity, while having a small average particle size and ζ-potential. The research results revealed the key role of SPI in maintaining the gel network and the significant enhancement effect of PP on protein cross-linking and gel properties. This finding helped to promote the more efficient and extensive application of plant protein in the food industry and other fields, and had important guiding significance for expanding the application scope of plant protein and improving product quality.
该研究调查了大豆分离蛋白（SPI）与马铃薯蛋白（PP）复合凝胶的凝胶特性及相互作用机制。结果表明，增加PP的比例可提高浊度和表面疏水性（H），促进从无规卷曲向β-折叠的转变，增强静电和疏水相互作用，并降低二硫键含量。这表明添加PP后复合凝胶的相互作用增强，形成了更复杂的二级结构。此外，蛋白质组学和电泳分析表明，特定的SPI亚基（P26987、Q96452、P02520、Q948P5、Q39839、P02580、P50346和P69325）在SPI/PP 70:30复合凝胶中发生不可逆变性，形成了新的蛋白质片段（30 - 45 kDa和70 - 90 kDa）。值得注意的是，SPI/PP 70:30复合凝胶具有最高的溶解度、持水能力（WHC）、储能模量（G'）值、结合水含量、凝胶强度和弹性，同时平均粒径和ζ电位较小。研究结果揭示了SPI在维持凝胶网络中的关键作用以及PP对蛋白质交联和凝胶特性的显著增强作用。这一发现有助于促进植物蛋白在食品工业等领域更高效、广泛的应用，对扩大植物蛋白的应用范围和提高产品质量具有重要的指导意义。
