School of Food Science and Engineering, Natural Food Macromolecule Research Center, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021, China.
School of Food Science and Engineering, Natural Food Macromolecule Research Center, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021, China.
Food Res Int. 2023 Feb;164:112355. doi: 10.1016/j.foodres.2022.112355. Epub 2022 Dec 26.
Effects of calcium gluconate (CG), calcium lactate (CL) and calcium dihydrogen phosphate (CDP) on the structural and functional properties of mung bean starch (MBS)-flaxseed protein (FP) composite gels were investigated to explore the feasibility of developing dysphagia food. The water-immobilizing, rheological and structural properties of MBS-FP composite gels adding different calcium salts (10, 30, and 50 mmol/L) were analyzed by low-field nuclear magnetic resonance measurement, rheological and textural analyses, fourier transform infrared spectroscopy, scanning electron microscopy and confocal laser scanning microscopy. Results showed that calcium salts imparted various soft gel properties to the composite gels by influencing the interactions between MBS and FP. Calcium salts could affect the conformation of amylose chains, accelerate the aggregation of FP molecules, and increase the cross-linking between starch and protein aggregates, resulting in the formation of large aggregates and a weak gel network. Consequently, calcium salts-induced composite gels showed lower viscoelastic moduli and gel strength than the control gel. In particular, different calcium salts had various impacts on the gel properties due to their diverse ability forming hydrogen bonds. Compared with CL and CDP, the gels containing CG presented the higher viscoelastic moduli and hardness, and possessed an irregular cellular network with the increased pore number and the decreased wall thickness. The gel containing 50 mmol/L CL had the highest water-holding capacity, in all the gels tested, by retaining more immobilized and mobile water in the compact gel network with larger cavities. The gels adding CDP presented lower hardness and gumminess due to the obvious lamellar structure within the network. International dysphagia diet standardization initiative (IDDSI) tests indicated that the gels adding CG and CL could be categorized into level 6 (soft and bite-sized) dysphagia diet, while the samples adding CDP could be classified into level 5 (minced and moist). These findings provide insights for the development of the novel soft gel-type dysphagia food.
研究了葡萄糖酸钙（CG）、乳酸钙（CL）和磷酸二氢钙（CDP）对绿豆淀粉（MBS）-亚麻籽蛋白（FP）复合凝胶结构和功能性质的影响，以期开发吞咽困难食品。采用低场核磁共振、流变和质构分析、傅里叶变换红外光谱、扫描电子显微镜和共聚焦激光扫描显微镜分析了添加不同钙盐（10、30 和 50 mmol/L）的 MBS-FP 复合凝胶的水固定、流变和结构性质。结果表明，钙盐通过影响 MBS 和 FP 之间的相互作用，赋予复合凝胶不同的软凝胶性质。钙盐可以影响直链淀粉链的构象，加速 FP 分子的聚集，并增加淀粉和蛋白质聚集之间的交联，导致形成大的聚集物和弱的凝胶网络。因此，与对照凝胶相比，钙盐诱导的复合凝胶表现出较低的黏弹性模量和凝胶强度。特别是，由于不同的形成氢键能力，不同的钙盐对凝胶性质有不同的影响。与 CL 和 CDP 相比，含有 CG 的凝胶表现出更高的黏弹性模量和硬度，并且具有不规则的蜂窝状网络，增加了孔数，减小了壁厚度。在所有测试的凝胶中，含有 50 mmol/L CL 的凝胶具有最高的持水能力，通过在具有较大空腔的致密凝胶网络中保留更多的固定水和可动水。由于网络内存在明显的层状结构，添加 CDP 的凝胶表现出较低的硬度和胶粘性。国际吞咽困难饮食标准化倡议（IDDSI）测试表明，添加 CG 和 CL 的凝胶可归类为 6 级（软质和一口大小）吞咽困难饮食，而添加 CDP 的样品可归类为 5 级（切碎和湿润）。这些发现为新型软凝胶型吞咽困难食品的开发提供了思路。
