School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China.
School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China.
Int J Biol Macromol. 2023 Sep 30;249:126003. doi: 10.1016/j.ijbiomac.2023.126003. Epub 2023 Jul 28.
The aim of this study is the effects of (+)-catechin (CC) covalent cross-linking (CCCI) (0.05-0.25 %, w/v) on the physicochemical properties, rheological properties, and oxidative stability of rice bran protein (RBP) emulsion. Analysis of particle size, ζ-potential, circular dichroism, fluorescence spectroscopy, surface hydrophobicity, and emulsifying properties demonstrated that a concentration of 0.15 % (w/v) CCCI facilitated protein structure unfolding, resulting in reduced particle size, enhanced electrostatic repulsion, and improved emulsion stability. Moreover, the covalent complexes of RBP-0.15 %CC (w/v) exhibited increased viscosity and shear stress, reflected by the highest G' and G″ values, ultimately enhancing the oxidative stability. Furthermore, analysis using atomic force microscopy and confocal laser scanning microscopy revealed that the RBP-0.15 %CC complexes exhibited the smallest particle size (164 nm) and displayed greater homogeneity. An increase in CC concentration to 0.25 % (w/v) resulted in a higher emulsion aggregation. The emulsions stabilized by CCCI exhibited superior rheological properties and enhanced oxidation stability compared to the control. In conclusion, an appropriate amount of CC can enhance the rheology and oxidation stability of the RBP emulsion, while CCCI treatment holds potential for expanding the utility of RBP in various applications.
本研究旨在探讨（+）-儿茶素（CC）共价交联（CCCI）（0.05-0.25%，w/v）对米糠蛋白（RBP）乳液的理化性质、流变性质和氧化稳定性的影响。通过分析粒径、ζ-电位、圆二色性、荧光光谱、表面疏水性和乳化性能表明，0.15%（w/v）CCCI 浓度有利于蛋白质结构展开，导致粒径减小、静电排斥增强、乳液稳定性提高。此外，RBP-0.15%CC（w/v）的共价复合物表现出更高的粘度和剪切应力，表现为最高的 G'和 G″值，最终增强了氧化稳定性。进一步通过原子力显微镜和共聚焦激光扫描显微镜分析表明，RBP-0.15%CC 复合物的粒径最小（164nm），且分布更均匀。CC 浓度增加到 0.25%（w/v）时，乳液的聚集程度更高。与对照相比，经 CCCI 稳定的乳液表现出更好的流变学性质和增强的氧化稳定性。综上所述，适量的 CC 可以增强 RBP 乳液的流变性和氧化稳定性，而 CCCI 处理有可能扩展 RBP 在各种应用中的用途。
