酪蛋白酸钠-燕麦β-葡聚糖美拉德产物的制备及其性质

Prepreparation and Properties of Sodium Caseinate-Oat β-Glucan conjugates by Maillard reaction

摘要:

以酪蛋白酸钠（Sodium Caseinate，SC）和燕麦β-葡聚糖(oat β-glucan，OG)利用干法美拉德反应制备酪蛋白酸钠-燕麦β-葡聚糖美拉德产物。利用单因素试验，以接枝度和褐变度为评价指标，对其制备条件进行研究，确定酪蛋白酸钠-燕麦β-葡聚糖美拉德产物最佳反应条件为：酪蛋白酸钠：燕麦β-葡聚糖为1:2，反应温度为60 ℃，反应时间为24 h，反应湿度为78 %，反应pH值为7。SDS-PAGE 电泳结果表明，酪蛋白酸钠和燕麦β-葡聚糖之间共价交联形成大分子聚合物。红外光谱分析表明糖苷键成功连接到蛋白质分子。内源荧光光谱表明引入多糖亲水性羟基，酪蛋白酸钠空间结构改变。最终得到美拉德产物的接枝度为50.01 %，褐变L值为85.06，乳化活性提高了85.12 %，乳化稳定性提高了11.24 %。本文改善了酪蛋白酸钠在一定pH范围内的溶解性和乳化性，拓展了酪蛋白酸钠在食品医药的应用范围。

Abstract:

The sodium caseinate-oat β-glucan conjugate was prepared by dry Maillard reaction with sodium caseinate (SC) and oat β-glucan (OG). Using single factor test, with the degree of grafting and degree of browning as evaluation indicators, the preparation conditions were studied, and the optimal reaction conditions of SC-OG conjugates were determined as follows: the ratio of SC and OG was 1:2, reaction temperature was 60 °C, reaction time was 24 h, reaction humidity was 78 %, reaction pH was 7. The results of SDS-PAGE electropHoresis showed that the covalent cross-linking between SC and OG formed macromolecular polymers. Infrared spectroscopic analysis indicated that the glycosidic bond was successfully attached to the protein molecule. Endogenous fluorescence spectra showed that the introduction of hydrophilic hydroxyl group of polysaccharide changed the spatial structure of sodium caseinate.Finally, the grafting degree of the obtained graft conjugate was 50.01 %, browning L value was 85.06, emulsification activity was increased by 85.12 %, and the emulsification stability was increased by 11.24 %.This paper improves the solubility and emulsification of sodium caseinate in a certain pH range, and expands the application scope of sodium caseinate in food and medicine.