发芽处理对玉米醇溶蛋白结构、热特性及乳化特性的影响  

Effect of Germinating Treatment on Structure,Thermal and Emulsifying Properties of Zein

作　　者：刘立鹏 方晓敏 姜鑫 修琳[1] 蔡丹[1] 刘景圣[1] Liu Lipeng;Fang Xiaomin;Jiang Xin;Xiu Lin;Cai Dan*;Liu Jingsheng(College of Food Science and Engineering,Jilin Agricultural University,National Engineering Research Centre for Deep Processing of Wheat and Corn,Changchun 130118)

机构地区：[1]吉林农业大学食品科学与工程学院小麦和玉米深加工国家工程研究中心,长春130118

出　　处：《中国食品学报》2024年第7期252-260,共9页Journal of Chinese Institute Of Food Science and Technology

基　　金：吉林省中青年科技创新创业卓越人才(团队)项目(创新类)(20230508014RC)。

摘　　要：为明确不同发芽处理时间对玉米籽粒中醇溶蛋白结构及特性的影响,以发芽处理不同时间的玉米籽粒中的玉米醇溶蛋白为研究对象,采用傅里叶红外衍射技术、X-射线衍射、SDS-聚丙烯酰胺凝胶电泳、差示热量扫描、游离巯基和二硫键分析发芽过程中玉米醇溶蛋白二级结构、结晶性、巯基、二硫键、热特性和乳化特性的变化。结果表明,发芽处理后的玉米醇溶蛋白的二级结构α-螺旋和β-转角结构分别降低了8.05%和9.08%,而β-折叠含量提升了4%~23%,同时发芽后蛋白二硫键发生断裂,游离巯基含量显著升高(P<0.05)。发芽后蛋白分子质量也发生变化,高分子质量蛋白条带向下偏移,低分子质量蛋白向上偏移且含量降低。X-射线衍射分析表明,发芽后玉米醇溶蛋白的结晶性发生改变,9°时的峰在发芽处理后期趋于平缓。差示热量扫描结果显示,处理后的玉米醇溶蛋白的变性温度平均提高了6.43℃。发芽处理的玉米醇溶蛋白的乳化性和乳化稳定性均有所提高,乳化性指数在发芽72 h时,提升了10.53 m^(2)/g,且乳化稳定性指数在发芽时间60 h时,与未发芽时相比提高了81.36 min。结论:适当的发芽处理可以修饰玉米醇溶蛋白结构,进而改善理化特性。In order to clarify the effects of different germination treatment time on the structure and characteristics of zein in corn grains,this paper took zein in corn grains with different germination treatment time as the research object.Fourier infrared diffraction,X-ray diffraction,SDS-polyacrylamide gel electrophoresis,differential thermal scanning,free sulfhydryl group and disulfide bond were used to analyze the secondary structure,crystallinity,sulfhydryl group,disulfide bond,thermal properties and emulsification properties of zein during germination.The results showed that the secondary structureα-helix andβ-corner structure of zein after germination were decreased by 8.05%and 9.08%,respectively,while theβ-fold content was increased by 4%-23%.Meanwhile,the disulfide bond was broken after germination,and the content of free sulfides was significantly increased(P<0.05).The molecular weight of proteins also changed after germination.The bands of high molecular weight proteins migrated downward,while the content of low molecular weight proteins migrated upward and decreased.X-ray diffraction analysis showed that the crystallinity of zein changed after germination,and the peak at 9°tended to be gentle at the later stage of germination.The DSC results showed that the denaturation temperature of zein was increased by 6.43℃ on average.The emulsification and emulsification stability of the germinated zein were improved,and the emulsification index was increased by 10.53 m^(2)/g at 72 h of germination,and the emulsification stability index was increased by 81.36 min at 60 h of germination compared with that at no germination.The results showed that proper germination treatment could modify the structure of zein and improve its physicochemical properties.

关 键 词：发芽 玉米醇溶蛋白 二级结构 热特性 乳化特性 

分 类 号：TS201.2[轻工技术与工程—食品科学]