蛋白质与多糖通过美拉德反应形成的复合物具有很好的乳化性，然而关于蛋白质/多糖美拉德产物在凝胶体系中应用的研究很少。本研究采用干热法将乳清分离蛋白（WPI）与不同分子量（20~210 ku）的大麦β-葡聚糖（BGL）制备成WPI-BGL美拉德产物，通过分光光度计测定褐变强度，利用荧光光谱分析结构，并探讨美拉德反应对WPI-BGL热凝胶流变性的影响。结果表明：WPI-BGL20的褐变强度最大，WPI-BGL的荧光强度都低于WPI，WPI与BGL发生美拉德反应使体系的结构发生很大改变。离子强度对WPI-BGL凝胶流变性有一定影响，WPI与BGL发生美拉德反应会降低WPI的凝胶G′，原因可能是在WPI-BGL体系中蛋白质分子间二硫键的形成和疏水相互作用受到了抑制，导致WPI-BGL凝胶的弱化。随着BGL分子量的减小，WPI-BGL的凝胶G′逐渐降低，这表明美拉德反应进程越大，形成的凝胶越弱。

Protein/polysaccharide conjugates obtained by Maillard reaction (MR) have good emulsifying properties. However, only few reports are available on the use of MR protein/polysaccharide gel systems. Whey protein isolate (WPI) and barley β-glucan (BGL) with different molecular weights (20~210 ku) were used to prepare WPI-BGL Maillard products by dry heat processing in this study. Browning intensity was measured by spectrophotometry, the structure was analyzed by fluorescence spectra, and the effect of MR on the rheological properties of WPI-BGL thermal gel was explored. The results showed that the browning intensity was highest for WPI-BGL20, the ionic strength affected the rheological properties of WPI-BGL gel, the fluorescence intensity of WPI-BGL samples was lower than that of WPI, and the MR between WPI and BGL resulted in a significant change in structure and a decrease in gel storage modulus (G'). This was possibly due to the suppression of disulfide bond formation between protein molecules and hydrophobic interactions in WPI-BGL systems, leading to weakening of the WPI-BGL gel. G' of the WPI-BGL gel reduced gradually with a decrease in BGL molecular weight, indicating that a greater extent of MR results in a weaker conjugate gel.

黑龙江省博士后基金（LBH-Z11237）；哈尔滨市应用技术研究与开发项目（2014RFQXJ123）