超声对燕麦蛋白氧化聚集体结构及特性的影响

Effect of Ultrasound on the Structure and Properties of Oat Protein Oxidized Aggregates

本研究以燕麦蛋白为原料,通过氧化剂偶氮二异丁脒盐酸盐(2,2′-azobis(2-amidinopropane),AAPH)氧化蛋白,将氧化蛋白分别进行不同超声功率(0、100、200、300、400、500、600 W)超声,以燕麦蛋白为对照,进行探究超声处理对蛋白结构特性(粒径、浊度、蛋白质分散指数值(Protein disperse index,PDI)、电位、二级结构、官能团、疏水性)和功能特性(溶解度、乳化活性和乳化稳定性)的影响。结果表明:与氧化燕麦蛋白聚集体相比,可溶性超声(功率500 W)燕麦氧化蛋白的平均粒径由855.33 nm降低到507.34 nm,PDI由0.97降低到0.26,浊度由543下降到267,表面疏水性和溶解度分别提高了1180.4和2.3%,乳化活性和乳化稳定性分别提高了207.95、361.48 m^2/g,二硫键含量降低了0.77 nmol/mg,β1-折叠结构降低,α-螺旋结构和无规卷曲结构提高,亚基含量增加。超声处理后氧化蛋白的乳化特性明显改善,且高于氧化后燕麦蛋白乳化性,这将为提高工业生产和降低企业损失提供方法和理论基础。

In this study,oat protein was used as raw material,and the oxidized protein was oxidized by oxidant azobisisobutyl hydrazine hydrochloride(2,2′-azobis(2-amidinopropane),AAPH),and the oxidized protein was ultrasonicated at different ultrasonic powers(0,100,200,300,400,500,600 W).Using oat protein as a control,the structure of the protein(particle size,turbidity,protein disperse index(PDI),potential,secondary structure,functional group,hydrophobicity)and functional properties(solubility,emulsification activity and emulsion stability).The results showed that compared with oxidized oat protein aggregates,the average particle size of soluble ultrasound(power 500 W)oat oxidized protein decreased from 855.33 nm to 507.34 nm,PDI decreased from 0.97 to 0.26,turbidity decreased from 543 to 267,surface hydrophobicity and solubility increased by 1180.4 and 2.3%,respectively.The emulsification activity and emulsion stability were increased by 207.95 and 361.48 m^2/g,the disulfide bond content was decreased by 0.77 nmol/mg,theβ1-folding structure was decreased,and theα-helical structure the random curl was improved,and the subunit content increased.The emulsification properties of the oxidized protein after the super-life treatment were significantly improved,and higher than the emulsification of the oat protein after oxidation,which provided a methodological and theoretical basis for improving industrial production and reducing enterprise losses.