Guo Na, Ma Ying, Zhang Fangyan, Zhu Guilan, Yu Zhenyu, Dai Huanhuan, Wang Ziying
Department of Life Science, Hefei Normal University, Hefei, Anhui, 230061, China.
School of tea and food science and technology, Anhui Agricultural University, Hefei, Anhui, 230601, China.
J Sci Food Agric. 2023 May;103(7):3346-3352. doi: 10.1002/jsfa.12512. Epub 2023 Mar 3.
Protein-polysaccharide gels have significant and unique properties in food formulations. However, they are susceptible to environmental influences like heat and pH. The present work investigated the effects of acid and alkali treatments on the gel properties and microstructural changes of whey protein isolate (WPI) high acyl gellan gum (HG).
The results showed that the pH had a strong effect on the gel hardness, water-holding capacity (WHC), free sulfhydryl groups (-SH), and other properties of the composite gel. The hardness reached a maximum level of 282.50 g and the best WHC was 98.33% at pH 7, indicating that a suitable pH could promote this cross-linking between the WPI and HG molecules. The rheological analysis demonstrated that the pH affected the gel formation time. Meanwhile, the gel formation time reached a maximum at pH 7, and the gel's storage modulus G' value was the largest in the final state. Fourier transform infrared spectroscopy (FTIR) results showed that pH affected the interaction between WPI and HG. Scanning electron microscopy (SEM) analysis also indicated that the composite gel formed a three-dimensional network structure at pH 7-9.
These results could broaden the application of protein-polysaccharide gels in food and delivery systems. © 2023 Society of Chemical Industry.
蛋白质 - 多糖凝胶在食品配方中具有显著且独特的性质。然而，它们易受热和pH等环境因素的影响。本研究考察了酸碱处理对乳清分离蛋白（WPI） - 高酰基结冷胶（HG）凝胶性质及微观结构变化的影响。
结果表明，pH对复合凝胶的凝胶硬度、持水能力（WHC）、游离巯基（-SH）及其他性质有显著影响。在pH 7时，硬度达到最高水平282.50 g，最佳持水能力为98.33%，表明合适的pH可促进WPI与HG分子之间的这种交联。流变学分析表明，pH影响凝胶形成时间。同时，凝胶形成时间在pH 7时达到最长，且凝胶最终状态下的储能模量G'值最大。傅里叶变换红外光谱（FTIR）结果表明，pH影响WPI与HG之间的相互作用。扫描电子显微镜（SEM）分析也表明，复合凝胶在pH 7 - 9时形成三维网络结构。
这些结果可拓宽蛋白质 - 多糖凝胶在食品和递送系统中的应用。© 2023化学工业协会。
