Acid/alkali shifting of Mesona chinensis polysaccharide-whey protein isolate gels: Characterization and formation mechanism. (1st September 2021)

• Record Type: Journal Article
• Authors: Jiang, Lian; Zhang, Jiahui; Ren, Yanming; Shen, Mingyue; Yu, Qiang; Chen, Yi; Zhang, Haide; Xie, Jianhua
• Is Part Of: Food chemistry. Volume 355(2021)
• Publication Date: 2021-09-01
• Subjects: Mesona chinensis polysaccharide -- Characterization -- Interactions -- Mechanism; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2021.129650
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Mesona chinensis polysaccharide and whey protein isolate formed a stable gel at pH10. Hydrophobic and hydrogen bond interactions are the main forces in composite gels. New hypocrystalline aggregates was formed in composite gels. Immobilized water was firmly locked in the network at pH10. Abstract: In this study, structural characteristics and formation mechanism of Mesona chinensis polysaccharide (MCP)-whey protein isolate (WPI) gels including group and molecular changes, intermolecular forces, crystallinity, and moisture migration were investigated under pH shifting conditions. Results showed that MCP and WPI formed a stable gel at pH 10. The free sulfhydryl groups and surface hydrophobicity of the MCP-WPI gels increased with the increasing pH. Hydrophobic and hydrogen bond interactions were the main molecular forces involved in the MCP-WPI gels, and electrostatic interactions and disulfide bonds played a complementary role. The pH conditions evidently influenced the secondary conformational structure of MCP-WPI gels. Molecular weight and X-ray diffraction (XRD) analysis indicated the formation of a hypocrystalline complex with molecular interaction. In addition, low-field magnetometry (LF-NMR) results showed that the T2 values decreased with increasing pH, indicating that water and gel matrix had the highest interactions at pH 10.