Comparison of the interfacial properties of native and refolded myofibrillar proteins subjected to pH-shifting. (30th June 2022)

• Record Type: Journal Article
• Authors: Lu, Junmeng; Zhang, Weiyi; Zhao, Xue; Xu, Xinglian
• Is Part Of: Food chemistry. Volume 380(2022)
• Publication Date: 2022-06-30
• Subjects: PSE-like -- Myofibrillar protein -- pH shifting -- Interfacial properties -- Emulsion -- Competitive desorption; ANS 8-anilinonaphthalene-1-sulfonate -- BCA bicinchoninic acid -- BSA bovine serum albumin -- β-ME β-mercaptoethanol -- CD circular dichroism -- Cf the concentration of unadsorbed protein -- CLSM confocal laser scanning microscopy -- PSE-like pale, soft, exudative-like -- MP myofibrillar protein -- SDS-PAGE sodium dodecyl sulfate-polyacrylamide gel electrophoresis -- SH sulfhydryl -- SS standard salt solution -- Г interfacial protein concentration; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2021.131734
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Refolded proteins exposed more hydrophobic groups and free sulfhydryl groups. The pH-shifting treatment increased adsorption of interfacial proteins. Emulsions stabilized by refolded proteins exhibited dispersed particle distribution. The pH shifting altered tertiary and secondary structures of interfacial proteins. MPs treated by pH 12.0 → 7.0 exhibited a multiple protein layer on oil surface. Abstract: The emulsion abilities of pale, soft, exudative (PSE)-like chicken breast protein are unsatisfied, which are urgently needed to be ameliorated. This study evaluated the improvement of pH-shifting (11.0-, 11.5- and 12.0–7.0) on emulsion properties of the PSE-like chicken breast myofibrillar proteins (MPs) and the underlined structure-driven interfacial mechanism. It was found pH-shifting promoted the exposure of buried hydrophobic groups and free sulfhydryl groups, and changed secondary structures. Emulsions stabilized by refolded MPs exhibited more uniform and dispersed distributions with more adsorbed proteins at the interface. Electrophorogram showed both disulfide and non-disulfide covalent bonds were involved during interfacial protein–protein interaction. The results from circular dichroism and front-surface fluorescence spectroscopy revealed interfacial MPs were exposed to a more hydrophobic environment and increased β-sheets enhanced their molecular interactions. In addition, interfacial proteins after pH-shifting was less likely to be replaced by Tween 20.