Abstract This study is aimed at designing of a composite cold-set hydrogel using whey protein isolate (WPI) and gellan gum as iron carrier. The effect of total polymer concentration (TPC) (0.5 and 1.5%), WPI/gellan ratio (1:1, 1:2, and 1:3), and iron concentration (10, 40, and 70 mM) on physicochemical and rheological characteristics of hydrogel were analyzed. By increasing TPC, the release mechanism became complex regarding less erosion of structure in simulated gastrointestinal medium. Moreover, the C O peak area of FTIR spectra was enhanced. As WPI/gellan ratio decreased, the faster release occurred due to a more porous structure. The cumulative release of iron in acidic and neutral pH increased up to 71.74 and 9.14%; however, iron was released up to 88.55 and 28.72% in simulated gastric and intestinal medium, respectively. The iron release followed a chemically-controlled mechanism in all samples. The area and number of gel pores and water-holding capacity decreased as Fe concentration was enhanced, but denaturation temperature increased. These results suggest that the strong texture with a solid elastic behavior along with a high cumulative release of iron made our hydrogel suitable for iron delivery to reduce iron deficiency-related disorders.

中文翻译：

---

用于铁截留的冷固化乳清蛋白-结冷胶水凝胶的命名和表征

摘要 本研究旨在设计一种以乳清分离蛋白（WPI）和结冷胶为铁载体的复合冷固水凝胶。总聚合物浓度 (TPC)（0.5% 和 1.5%）、WPI/结冷胶比率（1:1、1:2 和 1:3）和铁浓度（10、40 和 70 mM）对物理化学和分析了水凝胶的流变特性。通过增加 TPC，释放机制变得复杂，因为在模拟胃肠介质中结构的侵蚀较少。此外，FTIR 光谱的 CO 峰面积得到增强。随着 WPI/结冷胶比率降低，由于更多孔结构而发生更快的释放。酸性和中性pH条件下铁的累积释放量分别增加了71.74%和9.14%；然而，铁在模拟胃和肠介质中的释放率分别高达 88.55% 和 28.72%。在所有样品中，铁释放遵循化学控制机制。随着Fe浓度的增加，凝胶孔的面积和数量以及持水能力下降，但变性温度升高。这些结果表明，具有固体弹性行为的坚固质地以及铁的高累积释放使我们的水凝胶适合用于铁输送以减少缺铁相关疾病。