Effect of gamma irradiation on structural, molecular, thermal and rheological properties of sunflower protein isolate. (November 2017)

• Record Type: Journal Article
• Authors: Malik, Mudasir Ahmad; Sharma, Harish Kumar; Saini, Charanjiv Singh
• Is Part Of: Food hydrocolloids. Volume 72(2017)
• Page Start: 312
• Page End: 322
• Publication Date: 2017-11
• Subjects: Sunflower protein isolates -- Gamma irradiation -- Protein structure -- Molecular weight -- Thermal stability -- Rheological properties; Hydrocolloids -- Periodicals; Food additives -- Periodicals; Colloïdes -- Périodiques; Aliments -- Additifs -- Périodiques; Colloids; Food additives; Periodicals; Electronic journals; 664.06
• DOI: 10.1016/j.foodhyd.2017.06.011
• Languages: English
• ISSNs: 0268-005X

Abstract

Abstract: 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. Graphical abstract: Highlights: Secondary and tertiary structure of protein was changed after gamma irradiation. Thermal stability was improved due to crosslinking between protein molecules. SDS-PAGE and SE-HPLC showed increase in molecular weight of protein after irradiation. Elastic nature of protein gels was improved with gamma irradiation.