Middle East Technical University, Food Engineering Department, Ankara, Turkey.
Middle East Technical University, Food Engineering Department, Ankara, Turkey; Ahi Evran University, Food Engineering Department, Kirsehir, Turkey.
Int J Biol Macromol. 2020 Dec 1;164:2051-2061. doi: 10.1016/j.ijbiomac.2020.08.087. Epub 2020 Aug 12.
Quince seed powder (QSP) is known to exhibit emulsification properties and could be used as a natural emulsifier in colloidal food systems. In this study, emulsion-based alginate hydrogels were formulated using QSP and xanthan gum (XG) as stabilizers. The objective of the study was to show the emulsifying power of QSP in emulsions and their hydrogels using Time Domain (TD) NMR Relaxometry and Magnetic Resonance Imaging (MRI). Rheology and mean particle size measurements for emulsions and scanning electron microscope (SEM) experiments for hydrogels were further conducted as complementary methods. QSP containing emulsions were found to have longer T relaxation times than XG samples (p < 0.05). Addition of either QSP or XG produced a more pseudoplastic flow behavior (p < 0.05) on the emulsions. Relaxation times were also obtained by MR images through T maps. Relaxation decay curves showed the presence of two proton compartments in hydrogels; protons associated with the polymer matrix and protons interacting with the oil phase. The contribution of the first proton pools was the largest in QSP hydrogels confirmed by the lowest standard deviation in the T maps. This behavior was explained by the emulsification ability of QSP. Results showed that NMR Relaxometry and MR images could be used to understand the emulsifying nature of QSP and many other hydrocolloids.
绵葵花籽粉（QSP）具有乳化性能，可用作胶体食品体系中的天然乳化剂。本研究使用 QSP 和黄原胶（XG）作为稳定剂，制备基于乳液的海藻酸盐水凝胶。本研究的目的是使用时域（TD）NMR 弛豫和磁共振成像（MRI）来展示 QSP 在乳液及其水凝胶中的乳化能力。此外，还进行了流变学和乳液中平均粒径测量以及水凝胶的扫描电子显微镜（SEM）实验作为补充方法。含有 QSP 的乳液的 T 弛豫时间比 XG 样品长（p<0.05）。添加 QSP 或 XG 都会使乳液表现出更假塑性的流动行为（p<0.05）。弛豫时间也可以通过 T 图谱从 MR 图像中获得。弛豫衰减曲线显示水凝胶中有两个质子隔室；与聚合物基质结合的质子和与油相相互作用的质子。通过 T 图谱中的最低标准偏差证实 QSP 水凝胶中第一个质子池的贡献最大。这种行为是由 QSP 的乳化能力解释的。结果表明，NMR 弛豫和 MRI 可用于了解 QSP 和许多其他水胶体的乳化性质。
