Influence of Maillard conjugation on structural characteristics and rheological properties of whey protein/dextran systems
Influence of Maillard conjugation on structural characteristics and rheological properties of whey protein/dextran systems
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DOI：
10.1016/j.foodhyd.2014.01.014
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发表时间：
2014-08-01
影响因子：
10.7
通讯作者：
Carrara, Carlos R.
中科院分区：
文献类型：
--
作者：
Julia Spotti, Maria;Julia Martinez, Maria;Carrara, Carlos R.
众所周知，通过美拉德反应（MR）得到的蛋白质/多糖偶联物具有良好的乳化性能。然而，关于这些缀合物在凝胶体系中的应用的信息很少。研究了不同分子量（分子量分别为6、40和70 kDa）的乳清分离蛋白（WPI）和右旋糖酐（DX）的MR共轭物的结构特征和流变学性质。电泳证实偶联；通过420 nm处吸光度测定褐变强度；色氨酸（Trp） （λ (ex) = 280 nm）荧光发射研究构象变化。流变学性质由温度斜坡（25-90℃）振荡流变法测定。每次测量后，获得25℃时的力学谱。电泳结果表明，所有体系中均存在WPI/DX偶联物。褐变强度随DX分子量的减小而增大。WPI/DX孵育体系的荧光发射增强，而WPI/DX孵育体系的荧光发射减弱。与单独使用WPI相比，共轭体系在25℃下的凝胶时间（通过G′-G′交叉得到）和G′值增加。频率扫描显示了凝胶结构的稳定性。(C) 2014 Elsevier Ltd.版权所有。
It is well known that protein/polysaccharide conjugates obtained by Maillard reaction (MR) have good emulsifying properties. However, there is little information about the use of these conjugates in gel systems. Structural characteristics and rheological properties of conjugates obtained by MR of whey protein isolate (WPI) and dextrans (DX) of various molecular weight (MW: 6, 40 and 70 kDa) were studied. Conjugation was confirmed by electrophoresis; browning intensity was measured by absorbance at 420 nm; and conformational changes were studied by fluorescence emission of tryptophan (Trp) (lambda(ex) = 280 nm). Rheological properties were determined by oscillatory rheometry with temperature ramp (25-90 degrees C). After each measure, a mechanical spectrum (at 25 degrees C) was obtained. The electrophoresis indicated the presence of WPI/DX conjugates in all systems. Browning intensity increased with decreasing MW of DX. Fluorescence emission of WPI incubated increased, but decreased in WPI/DX incubated systems. The gelation time (obtained by G'-G '' crossover) and G' value at 25 degrees C increased in conjugate systems compared with WPI alone. Stability of gel structures were shown by frequency sweeps. (C) 2014 Elsevier Ltd. All rights reserved.