刘兴丽　杨龙松　赵双丽　吴凤　张华

摘要：以马铃薯蛋白（PP）和黄原胶（XG）为原料，通过研究不同pH值、热处理条件和PP/XG质量比确定马铃薯蛋白-黄原胶微凝胶（PP-XGM）的最佳制备条件，对该条件下制备的PP-XGM结构进行表征，以动力学稳定性指数（TSI）为指标对其乳化稳定性进行研究.结果表明：PP-XGM的最佳制备条件为PP/XG质量比1：1，pH值3.0，80 ℃热处理30 min;与PP-XG相比，PP-XGM的粒径更大，多分散系数更小，颗粒分布更均匀;与PP相比，PP-XG和PP-XGM的最大吸收波长λmax发生了不同程度的蓝移，且PP-XGM的荧光强度（FI）下降最显著;采用透射电镜发现PP-XGM呈核壳结构;在油相体积分数相同的条件下，PP-XGM的乳化稳定性较PP显著提高.

Abstract：

Potato protein （PP） and xanthan gum （XG） were used as raw materials.The optimal preparation conditions of xanthan gum microgel （PP-XGM） were determined through different pH value，heat treatment conditions，and potato protein/xanthan gum mass ratio.The structure of the PP-XGM prepared under this condition was characterized.The stability kinetic index was used as an indicator to study its emulsification stability.The results showed that the best preparation conditions for PP-XGM were PP/XG mass ratio of 1：1，pH value 3.0，and 80 ℃ water bath heating for 30 min.Compared with PP-XG，PP-XGM had larger particle size，smaller polydispersity coefficient and more uniform particle distribution.Compared with PP，the maximum absorption wavelength λmax of PP-XG and PP-XGM had a different degree of blue shift，and the fluorescence intensity FI of PP-XGM had the most significant decrease.Using projection electron microscopy，it was found that PP-XGM had a core-shell structure.Under the same oil phase volume fraction，the emulsion stability of PP-XGM was significantly higher than that of PP.

0 引言

馬铃薯蛋白（PP）为马铃薯淀粉加工后的副产物[1]，其氨基酸组成比例均衡，含有大多数谷物没有的赖氨酸，营养价值可与动物蛋白媲美[2].PP按相对分子质量大小可分为三部分：高相对分子质量蛋白、马铃薯糖蛋白、蛋白酶抑制剂[3].其中，马铃薯糖蛋白具有良好的凝胶形成性、起泡性、乳化性等功能性质[4].目前，我国对PP的研究较少且不深入，主要集中在淀粉废液中蛋白的分离、改性等方面.

微凝胶是通过生物大分子间的交联形成三维网络结构，同时保持大量的溶剂分子、尺寸在微米级及以下的凝胶颗粒[5].微凝胶在稳定乳液等方面有着广泛的应用，其制备方法主要包括静电复合法、喷射均质法等[6].其中，静电复合法是通过两种或两种以上聚合物间的静电吸引力而相互聚集，如通过阴离子多糖与带正电的蛋白质静……