Department of Food Science and Engineering, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran; Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland.
Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland.
Food Chem. 2021 Apr 16;342:128388. doi: 10.1016/j.foodchem.2020.128388. Epub 2020 Oct 15.
The surface modification of β-lactoglobulin amyloid fibrils (AFs) was investigated by performing the Maillard reaction with the free anomeric carbon of the maltodextrin in water at pH 9.0 and 90 °C. The bonding of maltodextrin to fibrils was confirmed by determining the free amino group content and the presence of final products from the Maillard reaction. The secondary structure of AFs was preserved as observed by circular dichroism analysis. Atomic force microscopy evidenced that prolonged heat treatment caused hydrolysis of the attached polysaccharide and consequently lowered the height of the fibrils from 8.0 nm (after 1 h) to 6.0 nm (after 24 h), which led to the reduction of hydrophilicity of resulting conjugate. Increasing the reaction time, however, resulted in the improvement of colloidal stability and decrease in turbidity ascribed to the increment of glycation degree, as well as, a decrease in the isoelectric point of the protein-based supramolecular object.
通过在 pH 9.0 和 90°C 的水中使麦芽糊精的游离端基碳与β-乳球蛋白原纤维（AFs）发生美拉德反应，研究了β-乳球蛋白原纤维的表面修饰。通过测定游离氨基含量和确定美拉德反应的终产物，证实了麦芽糊精与原纤维的结合。圆二色性分析表明，AFs 的二级结构得以保留。原子力显微镜证据表明，长时间的热处理会导致附着的多糖水解，从而使纤维的高度从 8.0nm（1 小时后）降低至 6.0nm（24 小时后），导致所得缀合物的亲水性降低。然而，随着反应时间的延长，由于糖化程度的增加，胶体稳定性提高，浊度降低，以及基于蛋白质的超分子客体的等电点降低，导致了纤维的高度降低。
