Qiao Dongling, Zhang Yuyan, Sun Farong, Yoo Michelle, Zhao Guohua, Zhang Binjia
Chongqing Key Laboratory of Speciality Food Co-Built by Sichuan and Chongqing, College of Food Science, Southwest University, Chongqing 400715, China.
China Tobacco Hubei Industrial Co., Ltd., Wuhan 430040, Hubei, China.
Food Chem. 2025 Mar 15;468:142476. doi: 10.1016/j.foodchem.2024.142476. Epub 2024 Dec 13.
Enhancement mechanism of ι-carrageenan on the network structure and gel-related properties of soy protein isolate (SPI)/λ-carrageenan system was investigated. Adding ι-carrageenan decreased SPI particles' size in nano-scale, reduced hydrophobic interactions by suppressing exposure of hydrophobic groups, and increased the disulfide bonds in SPI. With rising ι-carrageenan content (< 0.55 %), the interaction between ι-carrageenan and SPI was enhanced mainly through electrostatic interaction and hydrogen bond. Meanwhile, SPI particles were reduced and their stacking compactness was increased as well. These contributed to the improvement of network structure and thus increased weakly bonded water from 97.7 to 98.5 %, water holding capacity from 55.29 % to 61.70 % and gel hardness from 0.53 to 1.30 N. Higher ι-carrageenan content (> 0.55 %) induced micro-phase separation as shown by CLSM images, and led to reduction of gel hardness. These results favor the rational design and application of SPI-based gel systems with desired practical properties.
研究了ι-卡拉胶对大豆分离蛋白（SPI）/λ-卡拉胶体系网络结构和凝胶相关性质的增强机制。添加ι-卡拉胶可使SPI颗粒在纳米尺度上减小尺寸，通过抑制疏水基团的暴露减少疏水相互作用，并增加SPI中的二硫键。随着ι-卡拉胶含量的增加（<0.55%），ι-卡拉胶与SPI之间的相互作用主要通过静电相互作用和氢键增强。同时，SPI颗粒减小，其堆积紧密性也增加。这些有助于网络结构的改善，从而使弱结合水从97.7%增加到98.5%，持水能力从55.29%提高到61.70%，凝胶硬度从0.53 N提高到1.30 N。如CLSM图像所示，较高的ι-卡拉胶含量（>0.55%）会引起微相分离，并导致凝胶硬度降低。这些结果有利于合理设计和应用具有所需实际性能的基于SPI的凝胶体系。
