Protein isolates were prepared from sunflower meal using alkaline extraction technique and were irradiated at different doses (0, 10, 20, 30, 40 and 50 kGy). Sunflower protein isolates were evaluated for structural, molecular, thermal and rheological properties. Secondary structure of proteins was disrupted with decrease in α-helix content and concomitant increase in β-sheet content. The change in fluorescence spectra was observed indicating the alteration in tertiary structure of protein molecules mainly due to the conformational changes especially aggregation and crosslinking of protein molecules. Increase in thermal stability of protein after irradiation was found as determined by differential scanning calorimetry and thermal gravimetric analysis. Molecular weight of protein was increased in a dose dependent manner due to protein-protein crosslinking. Development of cracks on the surface of protein particle after irradiation was observed by scanning electron microscopy. Storage (G′) and loss modulus (G″) of protein dispersion was increased after gamma irradiation.

中文翻译：

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γ射线辐照对向日葵分离蛋白的结构，分子，热学和流变性质的影响

使用碱性提取技术从葵花粕中制备蛋白分离物，并以不同剂量（0、10、20、30、40和50 kGy）照射。对向日葵分离蛋白的结构，分子，热和流变特性进行了评估。蛋白质的二级结构被破坏，α-螺旋含量降低，β-sheet含量随之增加。观察到荧光光谱的变化，表明蛋白质分子的三级结构的变化主要是由于构象变化，尤其是蛋白质分子的聚集和交联。如通过差示扫描量热法和热重分析所确定的，发现辐照后蛋白质的热稳定性增加。由于蛋白质-蛋白质交联，蛋白质的分子量以剂量依赖性方式增加。通过扫描电子显微镜观察到辐照后蛋白质颗粒表面裂纹的发展。γ辐照后，蛋白质分散体的储存（G'）和损失模量（G''）增加。