College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, 225127, China.
Jiangsu Key Laboratory of Dairy Biotechnology and Safety Control, Yangzhou University, Yangzhou, Jiangsu, China.
J Food Sci. 2021 Apr;86(4):1228-1242. doi: 10.1111/1750-3841.15659. Epub 2021 Mar 1.
This study aimed to determine the effect of initial pH and temperature on whey protein gel formation via the Maillard reaction, including changes in gel structure, rheological and texture properties. The color changes in the whey protein and glucose gels were not significant with increasing heat temperature. High temperature and alkaline conditions promoted exposure to hydrophobic groups such as -SH, which accelerated protein aggregation and gel formation. Moreover, the increased particle size and additional hydrophobic groups contributed to higher elastic modulus (G') in the whey protein gel. Fluorescence measurements revealed that more tryptophan on the protein surface decreased with increasing temperature, which indicated that exposure to tryptophan could increase the hydrophobicity of the protein gels. Whey proteins formed stronger, gummier, more elastic, and more cohesive gels at 70 ℃ under initial pH 9 conditions, which also increased with the addition of fructose.
本研究旨在通过美拉德反应确定初始 pH 值和温度对乳清蛋白凝胶形成的影响，包括凝胶结构、流变学和质构特性的变化。随着热温度的升高，乳清蛋白和葡萄糖凝胶的颜色变化并不明显。高温和碱性条件促进了疏水性基团如 -SH 的暴露，这加速了蛋白质的聚集和凝胶的形成。此外，增加的颗粒大小和额外的疏水性基团导致乳清蛋白凝胶的弹性模量（G'）更高。荧光测量表明，随着温度的升高，蛋白质表面上的色氨酸减少，这表明色氨酸的暴露会增加蛋白质凝胶的疏水性。在初始 pH 值为 9 且温度为 70℃的条件下，乳清蛋白形成了更强、更粘、更有弹性和更有凝聚力的凝胶，并且随着果糖的添加而增加。
