超声处理对乳清蛋白致敏性及结构的影响

Effect of ultrasonic treatment on sensitization and structure of whey protein

通过不同超声时间对乳清分离蛋白进行处理,研究超声对乳清蛋白致敏性及结构的影响。在相同超声功率和间歇比条件下,进行不同时间的超声处理,通过间接竞争酶联免疫吸附法测定过敏原结合能力,采用紫外光谱、傅里叶红外光谱、荧光光谱研究乳清蛋白的空间结构及表面疏水性变化,并通过扫描电镜分析乳清蛋白微观结构分析。结果表明,超声处理后乳清蛋白致敏性有明显下降,超声处理10 min时致敏性最低,随着超声时间的延长,蛋白结构舒展,紫外吸收强度和内源荧光强度增加,表面疏水性增强,α-螺旋和无规则卷曲含量增加,游离巯基含量增加,二硫键含量降低。超声处理对乳清蛋白空间结构的改变可能是造成致敏性降低的主要原因,在乳清蛋白降敏研究方面具有理论研究价值。

The effect of ultrasonic treatment duration on the sensitization and structure of whey protein was investigated by subjecting it to different ultrasonic time intervals.Under constant conditions of ultrasonic power and intermittent ratio,varying durations of ultrasonic treatment were applied.The allergen binding ability was assessed using an indirect competitive ELISA method.The spatial structure and surface hydrophobicity of whey protein were analyzed through UV spectrum,Fourier transform infrared spectrum,and fluorescence spectrum measurements.Additionally,the microstructure of whey protein was examined using scanning electron microscopy.Results demonstrated a significant reduction in sensitization after ultrasonic treatment,with the lowest observed at 10 minutes post-treatment.As the duration of ultrasound increased,the protein structure elongated,UV absorption intensity and endogenous fluorescence intensity heightened,surface hydrophobicity intensified,α-helical and irregular curl content increased while free thiol content rose but disulfide bond content decreased.Alterations in the spatial structure induced by ultrasound treatment may be attributed as the primary cause for reduced sensitization,has theoretical value in whey protein desensitization studies.