College of Food Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, China.
College of Food Engineering, Harbin University of Commerce, Harbin, Heilongjiang 150028, China.
Food Chem. 2024 Feb 15;434:137433. doi: 10.1016/j.foodchem.2023.137433. Epub 2023 Sep 9.
The effect of different corn starch (CS) concentrations on the gel formation of soybean isolate protein (SPI) was investigated. Moreover, the texture, rheological properties of the gel were determined, and the spatial structure and interactions of the composite gel system were analyzed. The composite system transitioned from liquid to solid-like with an increase in the CS concentration and did not backflow when inverted for 24 h. With the addition of CS, the gel strength, water holding capacity (WHC), G', and G'' increased significantly. The maximum was reached at 10 % starch concentration with gel strength of (228.96 ± 29.86) g and WHC of (98.93 ± 2.02) %. According to low-field H nuclear magnetic resonance (LF-NMR) results, CS has a high water absorption capacity, which improved the WHC. The scanning electron microscopy results revealed that composite gels with a high CS concentration had a more dense and small void network structure. According to the results of molecular force interaction, infrared spectroscopy, Raman spectroscopy, and free sulfhydryl group analysis, the added starch promoted the unfolding of SPI molecules, exposure of hydrophobic groups, transformation of free sulfhydryl groups into disulfide bonds, and hydrogen bond formation. Hydrophobic interactions, disulfide bonding, and hydrogen bonding function together to form the SPI-CS composite gel system. The study results provide the basis for applying soy protein and CS gels.
研究了不同玉米淀粉（CS）浓度对大豆分离蛋白（SPI）凝胶形成的影响。此外，还测定了凝胶的质构、流变特性，并分析了复合凝胶体系的空间结构和相互作用。随着 CS 浓度的增加，复合体系从液体向固态转变，倒置 24 小时后不会回流。随着 CS 的加入，凝胶强度、持水能力（WHC）、G'和 G''显著增加。在淀粉浓度为 10%时达到最大值，凝胶强度为（228.96±29.86）g，WHC 为（98.93±2.02）%。根据低场氢核磁共振（LF-NMR）结果，CS 具有高吸水性，提高了 WHC。扫描电子显微镜结果表明，高 CS 浓度的复合凝胶具有更致密和小的空隙网络结构。根据分子力相互作用、红外光谱、拉曼光谱和游离巯基分析的结果，添加的淀粉促进了 SPI 分子的展开、疏水性基团的暴露、游离巯基向二硫键的转化以及氢键的形成。疏水相互作用、二硫键和氢键共同作用形成了 SPI-CS 复合凝胶体系。研究结果为应用大豆蛋白和 CS 凝胶提供了依据。
